import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import android.widget.Toast;
import tabs.SlidingTablayout;
public class NewsFeed extends ActionBarActivity {
private Toolbar toolbar;
NavigationDrawer drawerFragment;
private ViewPager mPager;
private SlidingTablayout mTabs;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_appbar);
toolbar=(Toolbar)findViewById(R.id.app_bar);
setSupportActionBar(toolbar);
drawerFragment=new NavigationDrawer();
getSupportFragmentManager().findFragmentById(R.id.fragment_navigation_drawer);
drawerFragment.setUp((DrawerLayout) findViewById(R.id.drawer_layout), toolbar);
mPager=(ViewPager) findViewById(R.id.pager);
mPager.setAdapter(new myPagerAdapter(getSupportFragmentManager()));
mTabs=(SlidingTablayout) findViewById(R.id.tabs);
mTabs.setViewPager(mPager);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater menuInflater= getMenuInflater();
menuInflater.inflate(R.menu.activity_actionbar, menu);
return super.onCreateOptionsMenu(menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.search_id) {
Toast msg = Toast.makeText(NewsFeed.this, "search selected", Toast.LENGTH_SHORT);
msg.show();
return true;
}
if (id==R.id.info_id){
Toast msg = Toast.makeText(NewsFeed.this, "info selected", Toast.LENGTH_SHORT);
msg.show();
return true;
}
return super.onOptionsItemSelected(item);
}
class myPagerAdapter extends FragmentPagerAdapter{
String[] tabs;
public myPagerAdapter(FragmentManager fm) {
super(fm);
tabs=getResources().getStringArray(R.array.tabs);
}
@Override
public Fragment getItem(int position) {
MyFragment myFragment=MyFragment.getInstance(position);
return myFragment;
}
@Override
public CharSequence getPageTitle(int position) {
return tabs[position];
}
@Override
public int getCount() {
return 3;
}
}
public static class MyFragment extends Fragment{
private TextView textView;
public static MyFragment getInstance(int position){
MyFragment myFragment=new MyFragment();
Bundle args=new Bundle();
args.putInt("position",position);
myFragment.setArguments(args);
return myFragment;
}
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View layout=inflater.inflate(R.layout.fragment_my, container, false);
textView=(TextView) layout.findViewById(R.id.position);
Bundle bundle=getArguments();
if(bundle!=null){
textView.setText("The Page currently Selecte"+bundle.getInt("position"));
}
return layout;
}
}
}
这是我的滑动tablayout.java类
package tabs;
import android.content.Context;
import android.graphics.Typeface;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.util.SparseArray;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.TextView;
public class SlidingTablayout extends HorizontalScrollView {
public interface TabColorizer {
int getIndicatorColor(int position);
}
private static final int TITLE_OFFSET_DIPS = 24;
private static final int TAB_VIEW_PADDING_DIPS = 16;
private static final int TAB_VIEW_TEXT_SIZE_SP = 12;
private int mTitleOffset;
private int mTabViewLayoutId;
private int mTabViewTextViewId;
private boolean mDistributeEvenly;
private ViewPager mViewPager;
private SparseArray<String> mContentDescriptions = new SparseArray<String>();
private ViewPager.OnPageChangeListener mViewPagerPageChangeListener;
private final SlidingTabStrip mTabStrip;
public SlidingTablayout(Context context) {
this(context, null);
}
public SlidingTablayout(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public SlidingTablayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
setHorizontalScrollBarEnabled(false);
setFillViewport(true);
mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);
mTabStrip = new SlidingTabStrip(context);
addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
}
public void setCustomTabColorizer(TabColorizer tabColorizer) {
mTabStrip.setCustomTabColorizer(tabColorizer);
}
public void setDistributeEvenly(boolean distributeEvenly) {
mDistributeEvenly = distributeEvenly;
}
public void setSelectedIndicatorColors(int... colors) {
mTabStrip.setSelectedIndicatorColors(colors);
}
public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) {
mViewPagerPageChangeListener = listener;
}
public void setCustomTabView(int layoutResId, int textViewId) {
mTabViewLayoutId = layoutResId;
mTabViewTextViewId = textViewId;
}
public void setViewPager(ViewPager viewPager) {
mTabStrip.removeAllViews();
mViewPager = viewPager;
if (viewPager != null) {
viewPager.setOnPageChangeListener(new InternalViewPagerListener());
populateTabStrip();
}
}
protected TextView createDefaultTabView(Context context) {
TextView textView = new TextView(context);
textView.setGravity(Gravity.CENTER);
textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
textView.setTypeface(Typeface.DEFAULT_BOLD);
textView.setLayoutParams(new LinearLayout.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
TypedValue outValue = new TypedValue();
getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
outValue, true);
textView.setBackgroundResource(outValue.resourceId);
textView.setAllCaps(true);
int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
textView.setPadding(padding, padding, padding, padding);
return textView;
}
private void populateTabStrip() {
final PagerAdapter adapter = mViewPager.getAdapter();
final View.OnClickListener tabClickListener = new TabClickListener();
for (int i = 0; i < adapter.getCount(); i++) {
View tabView = null;
TextView tabTitleView = null;
if (mTabViewLayoutId != 0) {
tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip,
false);
tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
}
if (tabView == null) {
tabView = createDefaultTabView(getContext());
}
if (tabTitleView == null && TextView.class.isInstance(tabView)) {
tabTitleView = (TextView) tabView;
}
if (mDistributeEvenly) {
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams();
lp.width = 0;
lp.weight = 1;
}
tabTitleView.setText(adapter.getPageTitle(i));
tabView.setOnClickListener(tabClickListener);
String desc = mContentDescriptions.get(i, null);
if (desc != null) {
tabView.setContentDescription(desc);
}
mTabStrip.addView(tabView);
if (i == mViewPager.getCurrentItem()) {
tabView.setSelected(true);
}
}
}
public void setContentDescription(int i, String desc) {
mContentDescriptions.put(i, desc);
}
@Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
if (mViewPager != null) {
scrollToTab(mViewPager.getCurrentItem(), 0);
}
}
private void scrollToTab(int tabIndex, int positionOffset) {
final int tabStripChildCount = mTabStrip.getChildCount();
if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) {
return;
}
View selectedChild = mTabStrip.getChildAt(tabIndex);
if (selectedChild != null) {
int targetScrollX = selectedChild.getLeft() + positionOffset;
if (tabIndex > 0 || positionOffset > 0) {
targetScrollX -= mTitleOffset;
}
scrollTo(targetScrollX, 0);
}
}
private class InternalViewPagerListener implements ViewPager.OnPageChangeListener {
private int mScrollState;
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
int tabStripChildCount = mTabStrip.getChildCount();
if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) {
return;
}
mTabStrip.onViewPagerPageChanged(position, positionOffset);
View selectedTitle = mTabStrip.getChildAt(position);
int extraOffset = (selectedTitle != null)
? (int) (positionOffset * selectedTitle.getWidth())
: 0;
scrollToTab(position, extraOffset);
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageScrolled(position, positionOffset,
positionOffsetPixels);
}
}
@Override
public void onPageScrollStateChanged(int state) {
mScrollState = state;
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageScrollStateChanged(state);
}
}
@Override
public void onPageSelected(int position) {
if (mScrollState == ViewPager.SCROLL_STATE_IDLE) {
mTabStrip.onViewPagerPageChanged(position, 0f);
scrollToTab(position, 0);
}
for (int i = 0; i < mTabStrip.getChildCount(); i++) {
mTabStrip.getChildAt(i).setSelected(position == i);
}
if (mViewPagerPageChangeListener != null) {
mViewPagerPageChangeListener.onPageSelected(position);
}
}
}
private class TabClickListener implements View.OnClickListener {
@Override
public void onClick(View v) {
for (int i = 0; i < mTabStrip.getChildCount(); i++) {
if (v == mTabStrip.getChildAt(i)) {
mViewPager.setCurrentItem(i);
return;
}
}
}
}
} 这是我的slidingtabstrip代码
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import android.widget.LinearLayout;
class SlidingTabStrip extends LinearLayout {
private static final int DEFAULT_BOTTOM_BORDER_THICKNESS_DIPS = 0;
private static final byte DEFAULT_BOTTOM_BORDER_COLOR_ALPHA = 0x26;
private static final int SELECTED_INDICATOR_THICKNESS_DIPS = 3;
private static final int DEFAULT_SELECTED_INDICATOR_COLOR = 0xFF33B5E5;
private final int mBottomBorderThickness;
private final Paint mBottomBorderPaint;
private final int mSelectedIndicatorThickness;
private final Paint mSelectedIndicatorPaint;
private int mSelectedPosition;
private float mSelectionOffset;
private SlidingTablayout.TabColorizer mCustomTabColorizer;
private final SimpleTabColorizer mDefaultTabColorizer;
SlidingTabStrip(Context context) {
this(context, null);
}
SlidingTabStrip(Context context, AttributeSet attrs) {
super(context, attrs);
setWillNotDraw(false);
final float density = getResources().getDisplayMetrics().density;
TypedValue outValue = new TypedValue();
context.getTheme().resolveAttribute(android.R.attr.colorForeground, outValue, true);
final int themeForegroundColor = outValue.data;
int defaultBottomBorderColor = setColorAlpha(themeForegroundColor,
DEFAULT_BOTTOM_BORDER_COLOR_ALPHA);
mDefaultTabColorizer = new SimpleTabColorizer();
mDefaultTabColorizer.setIndicatorColors(DEFAULT_SELECTED_INDICATOR_COLOR);
mBottomBorderThickness = (int) (DEFAULT_BOTTOM_BORDER_THICKNESS_DIPS * density);
mBottomBorderPaint = new Paint();
mBottomBorderPaint.setColor(defaultBottomBorderColor);
mSelectedIndicatorThickness = (int) (SELECTED_INDICATOR_THICKNESS_DIPS * density);
mSelectedIndicatorPaint = new Paint();
}
void setCustomTabColorizer(SlidingTablayout.TabColorizer customTabColorizer) {
mCustomTabColorizer = customTabColorizer;
invalidate();
}
void setSelectedIndicatorColors(int... colors) {
mCustomTabColorizer = null;
mDefaultTabColorizer.setIndicatorColors(colors);
invalidate();
}
void onViewPagerPageChanged(int position, float positionOffset) {
mSelectedPosition = position;
mSelectionOffset = positionOffset;
invalidate();
}
@Override
protected void onDraw(Canvas canvas) {
final int height = getHeight();
final int childCount = getChildCount();
final SlidingTablayout.TabColorizer tabColorizer = mCustomTabColorizer != null
? mCustomTabColorizer
: (SlidingTablayout.TabColorizer) mDefaultTabColorizer;
if (childCount > 0) {
View selectedTitle = getChildAt(mSelectedPosition);
int left = selectedTitle.getLeft();
int right = selectedTitle.getRight();
int color = tabColorizer.getIndicatorColor(mSelectedPosition);
if (mSelectionOffset > 0f && mSelectedPosition < (getChildCount() - 1)) {
int nextColor = tabColorizer.getIndicatorColor(mSelectedPosition + 1);
if (color != nextColor) {
color = blendColors(nextColor, color, mSelectionOffset);
}
View nextTitle = getChildAt(mSelectedPosition + 1);
left = (int) (mSelectionOffset * nextTitle.getLeft() +
(1.0f - mSelectionOffset) * left);
right = (int) (mSelectionOffset * nextTitle.getRight() +
(1.0f - mSelectionOffset) * right);
}
mSelectedIndicatorPaint.setColor(color);
canvas.drawRect(left, height - mSelectedIndicatorThickness, right,
height, mSelectedIndicatorPaint);
}
// Thin underline along the entire bottom edge
canvas.drawRect(0, height - mBottomBorderThickness, getWidth(), height, mBottomBorderPaint);
}
private static int setColorAlpha(int color, byte alpha) {
return Color.argb(alpha, Color.red(color), Color.green(color), Color.blue(color));
}
private static int blendColors(int color1, int color2, float ratio) {
final float inverseRation = 1f - ratio;
float r = (Color.red(color1) * ratio) + (Color.red(color2) * inverseRation);
float g = (Color.green(color1) * ratio) + (Color.green(color2) * inverseRation);
float b = (Color.blue(color1) * ratio) + (Color.blue(color2) * inverseRation);
return Color.rgb((int) r, (int) g, (int) b);
}
private static class SimpleTabColorizer implements SlidingTablayout.TabColorizer {
private int[] mIndicatorColors;
@Override
public final int getIndicatorColor(int position) {
return mIndicatorColors[position % mIndicatorColors.length];
}
void setIndicatorColors(int... colors) {
mIndicatorColors = colors;
}
}
}
这是我的LogCat
02-29 22:37:41.472 6653-6653/com.example.mubbasher.howdy_sendgreetings D/dalvikvm: Late-enabling CheckJNI
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings I/dalvikvm: Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.internal.widget.TintTypedArray.getChangingConfigurations
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings W/dalvikvm: VFY: unable to resolve virtual method 373: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings D/dalvikvm: VFY: replacing opcode 0x6e at 0x0002
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings I/dalvikvm: Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.internal.widget.TintTypedArray.getType
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings W/dalvikvm: VFY: unable to resolve virtual method 395: Landroid/content/res/TypedArray;.getType (I)I
02-29 22:37:41.752 6653-6653/com.example.mubbasher.howdy_sendgreetings D/dalvikvm: VFY: replacing opcode 0x6e at 0x0002
02-29 22:37:41.862 6653-6653/com.example.mubbasher.howdy_sendgreetings D/AndroidRuntime: Shutting down VM
02-29 22:37:41.862 6653-6653/com.example.mubbasher.howdy_sendgreetings W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x41754c08)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: FATAL EXCEPTION: main
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: Process: com.example.mubbasher.howdy_sendgreetings, PID: 6653
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.mubbasher.howdy_sendgreetings/com.example.mubbasher.howdy_sendgreetings.NewsFeed}: java.lang.NullPointerException
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2436)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2498)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.access$900(ActivityThread.java:179)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1324)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.os.Looper.loop(Looper.java:146)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5641)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1288)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1104)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: Caused by: java.lang.NullPointerException
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at com.example.mubbasher.howdy_sendgreetings.NewsFeed.onCreate(NewsFeed.java:44)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.Activity.performCreate(Activity.java:5484)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1093)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2400)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2498)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.access$900(ActivityThread.java:179)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1324)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:102)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.os.Looper.loop(Looper.java:146)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5641)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:515)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1288)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1104)
02-29 22:37:41.872 6653-6653/com.example.mubbasher.howdy_sendgreetings E/AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
请帮帮我
答案 0 :(得分：0)
mTabs=(SlidingTablayout) findViewById(R.id.tabs);
mTabs.setViewPager(mPager);
您的mTabs正在投掷NPE。请重新检查一次SlidingTablayout的id，或者在xml中使用SlidingTablayout的完全限定名称，在xml中定义它。