Question

这是我的xml：
其实我正在制作照片编辑的应用程序，当我点击底部的编辑菜单弹出列表与不同的图像过滤器点击并应用。我想做任何帮助或参考将不胜感激

ListViewDemo.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_gravity="bottom"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#fff"
>
<com.example.horizontallistview_snapit.HorizontalListView
  android:id="@+id/listview"
  android:layout_width="fill_parent"
  android:layout_gravity="bottom"
  android:layout_height="wrap_content"
  android:background="#ddd" 
/>
</LinearLayout>

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="bottom"
>
<TextView  
android:layout_width="fill_parent" 
android:layout_height="wrap_content" 
android:text="@string/hello_world"
/>

viewitem.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#fff"
>
<ImageView
 android:id="@+id/image"
  android:layout_width="150dip"
  android:layout_height="150dip"
  android:scaleType="centerCrop"
  android:src="@drawable/ic_launcher"
  />
  <TextView
  android:id="@+id/title"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:textColor="#000"
  android:gravity="center_horizontal"
  />
  <Button
      android:id="@+id/clickbutton"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:text="Click Me"
      android:textColor="#000" />

  </LinearLayout>

HorizontalListView.java

    import java.util.LinkedList;
import java.util.Queue;

import android.content.Context;
import android.database.DataSetObserver;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.Scroller;

public class HorizontalListView extends AdapterView<ListAdapter> {

    public boolean mAlwaysOverrideTouch = true;
    protected ListAdapter mAdapter;
    private int mLeftViewIndex = -1;
    private int mRightViewIndex = 0;
    protected int mCurrentX;
    protected int mNextX;
    private int mMaxX = Integer.MAX_VALUE;
    private int mDisplayOffset = 0;
    protected Scroller mScroller;
    private GestureDetector mGesture;
    private Queue<View> mRemovedViewQueue = new LinkedList<View>();
    private OnItemSelectedListener mOnItemSelected;
    private OnItemClickListener mOnItemClicked;
    private OnItemLongClickListener mOnItemLongClicked;
    private boolean mDataChanged = false;


    public HorizontalListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initView();
    }

    private synchronized void initView() {
        mLeftViewIndex = -1;
        mRightViewIndex = 0;
        mDisplayOffset = 0;
        mCurrentX = 0;
        mNextX = 0;
        mMaxX = Integer.MAX_VALUE;
        mScroller = new Scroller(getContext());
        mGesture = new GestureDetector(getContext(), mOnGesture);
    }

    @Override
    public void setOnItemSelectedListener(AdapterView.OnItemSelectedListener listener) {
        mOnItemSelected = listener;
    }

    @Override
    public void setOnItemClickListener(AdapterView.OnItemClickListener listener){
        mOnItemClicked = listener;
    }

    @Override
    public void setOnItemLongClickListener(AdapterView.OnItemLongClickListener listener) {
        mOnItemLongClicked = listener;
    }

    private DataSetObserver mDataObserver = new DataSetObserver() {

        @Override
        public void onChanged() {
            synchronized(HorizontalListView.this){
                mDataChanged = true;
            }
            invalidate();
            requestLayout();
        }

        @Override
        public void onInvalidated() {
            reset();
            invalidate();
            requestLayout();
        }

    };

    @Override
    public ListAdapter getAdapter() {
        return mAdapter;
    }

    @Override
    public View getSelectedView() {
        //TODO: implement
        return null;
    }

    @Override
    public void setAdapter(ListAdapter adapter) {
        if(mAdapter != null) {
            mAdapter.unregisterDataSetObserver(mDataObserver);
        }
        mAdapter = adapter;
        mAdapter.registerDataSetObserver(mDataObserver);
        reset();
    }

    private synchronized void reset(){
        initView();
        removeAllViewsInLayout();
        requestLayout();
    }

    @Override
    public void setSelection(int position) {
        //TODO: implement
    }

    private void addAndMeasureChild(final View child, int viewPos) {
        LayoutParams params = child.getLayoutParams();
        if(params == null) {
            params = new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
        }

        addViewInLayout(child, viewPos, params, true);
        child.measure(MeasureSpec.makeMeasureSpec(getWidth(), MeasureSpec.AT_MOST),
                MeasureSpec.makeMeasureSpec(getHeight(), MeasureSpec.AT_MOST));
    }



    @Override
    protected synchronized void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);

        if(mAdapter == null){
            return;
        }

        if(mDataChanged){
            int oldCurrentX = mCurrentX;
            initView();
            removeAllViewsInLayout();
            mNextX = oldCurrentX;
            mDataChanged = false;
        }

        if(mScroller.computeScrollOffset()){
            int scrollx = mScroller.getCurrX();
            mNextX = scrollx;
        }

        if(mNextX <= 0){
            mNextX = 0;
            mScroller.forceFinished(true);
        }
        if(mNextX >= mMaxX) {
            mNextX = mMaxX;
            mScroller.forceFinished(true);
        }

        int dx = mCurrentX - mNextX;

        removeNonVisibleItems(dx);
        fillList(dx);
        positionItems(dx);

        mCurrentX = mNextX;

        if(!mScroller.isFinished()){
            post(new Runnable(){
                @Override
                public void run() {
                    requestLayout();
                }
            });

        }
    }

    private void fillList(final int dx) {
        int edge = 0;
        View child = getChildAt(getChildCount()-1);
        if(child != null) {
            edge = child.getRight();
        }
        fillListRight(edge, dx);

        edge = 0;
        child = getChildAt(0);
        if(child != null) {
            edge = child.getLeft();
        }
        fillListLeft(edge, dx);


    }

    private void fillListRight(int rightEdge, final int dx) {
        while(rightEdge + dx < getWidth() && mRightViewIndex < mAdapter.getCount()) {

            View child = mAdapter.getView(mRightViewIndex, mRemovedViewQueue.poll(), this);
            addAndMeasureChild(child, -1);
            rightEdge += child.getMeasuredWidth();

            if(mRightViewIndex == mAdapter.getCount()-1) {
                mMaxX = mCurrentX + rightEdge - getWidth();
            }

            if (mMaxX < 0) {
                mMaxX = 0;
            }
            mRightViewIndex++;
        }

    }

    private void fillListLeft(int leftEdge, final int dx) {
        while(leftEdge + dx > 0 && mLeftViewIndex >= 0) {
            View child = mAdapter.getView(mLeftViewIndex, mRemovedViewQueue.poll(), this);
            addAndMeasureChild(child, 0);
            leftEdge -= child.getMeasuredWidth();
            mLeftViewIndex--;
            mDisplayOffset -= child.getMeasuredWidth();
        }
    }

    private void removeNonVisibleItems(final int dx) {
        View child = getChildAt(0);
        while(child != null && child.getRight() + dx <= 0) {
            mDisplayOffset += child.getMeasuredWidth();
            mRemovedViewQueue.offer(child);
            removeViewInLayout(child);
            mLeftViewIndex++;
            child = getChildAt(0);

        }

        child = getChildAt(getChildCount()-1);
        while(child != null && child.getLeft() + dx >= getWidth()) {
            mRemovedViewQueue.offer(child);
            removeViewInLayout(child);
            mRightViewIndex--;
            child = getChildAt(getChildCount()-1);
        }
    }

    private void positionItems(final int dx) {
        if(getChildCount() > 0){
            mDisplayOffset += dx;
            int left = mDisplayOffset;
            for(int i=0;i<getChildCount();i++){
                View child = getChildAt(i);
                int childWidth = child.getMeasuredWidth();
                child.layout(left, 0, left + childWidth, child.getMeasuredHeight());
                left += childWidth + child.getPaddingRight();
            }
        }
    }

    public synchronized void scrollTo(int x) {
        mScroller.startScroll(mNextX, 0, x - mNextX, 0);
        requestLayout();
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        boolean handled = super.dispatchTouchEvent(ev);
        handled |= mGesture.onTouchEvent(ev);
        return handled;
    }

    protected boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
                float velocityY) {
        synchronized(HorizontalListView.this){
            mScroller.fling(mNextX, 0, (int)-velocityX, 0, 0, mMaxX, 0, 0);
        }
        requestLayout();

        return true;
    }

    protected boolean onDown(MotionEvent e) {
        mScroller.forceFinished(true);
        return true;
    }

    private OnGestureListener mOnGesture = new GestureDetector.SimpleOnGestureListener() {

        @Override
        public boolean onDown(MotionEvent e) {
            return HorizontalListView.this.onDown(e);
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
                float velocityY) {
            return HorizontalListView.this.onFling(e1, e2, velocityX, velocityY);
        }

        @Override
        public boolean onScroll(MotionEvent e1, MotionEvent e2,
                float distanceX, float distanceY) {

            synchronized(HorizontalListView.this){
                mNextX += (int)distanceX;
            }
            requestLayout();

            return true;
        }

        @Override
        public boolean onSingleTapConfirmed(MotionEvent e) {
            for(int i=0;i<getChildCount();i++){
                View child = getChildAt(i);
                if (isEventWithinView(e, child)) {
                    if(mOnItemClicked != null){
                        mOnItemClicked.onItemClick(HorizontalListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i ));
                    }
                    if(mOnItemSelected != null){
                        mOnItemSelected.onItemSelected(HorizontalListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId( mLeftViewIndex + 1 + i ));
                    }
                    break;
                }

            }
            return true;
        }

        @Override
        public void onLongPress(MotionEvent e) {
            int childCount = getChildCount();
            for (int i = 0; i < childCount; i++) {
                View child = getChildAt(i);
                if (isEventWithinView(e, child)) {
                    if (mOnItemLongClicked != null) {
                        mOnItemLongClicked.onItemLongClick(HorizontalListView.this, child, mLeftViewIndex + 1 + i, mAdapter.getItemId(mLeftViewIndex + 1 + i));
                    }
                    break;
                }

            }
        }

        private boolean isEventWithinView(MotionEvent e, View child) {
            Rect viewRect = new Rect();
            int[] childPosition = new int[2];
            child.getLocationOnScreen(childPosition);
            int left = childPosition[0];
            int right = left + child.getWidth();
            int top = childPosition[1];
            int bottom = top + child.getHeight();
            viewRect.set(left, top, right, bottom);
            return viewRect.contains((int) e.getRawX(), (int) e.getRawY());
        }
    };
}     

**HorizontalListViewDemo.java**    

import android.app.Activity;
import android.app.AlertDialog;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.TextView;

public class HorizontalListViewDemo extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.listviewdemo);

        HorizontalListView listview = (HorizontalListView) findViewById(R.id.listview);
        listview.setAdapter(mAdapter);


    }

    private static String[] dataObjects = new String[]{ "Text #1",
        "Text #2",
        "Text #3","Text #4","Text #5","Text #6","Text #7","Text #8","Text #9","Text #10" }; 

    private BaseAdapter mAdapter = new BaseAdapter() {

        private OnClickListener mOnButtonClicked = new OnClickListener() {

            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder = new AlertDialog.Builder(HorizontalListViewDemo.this);
                builder.setMessage("hello from " + v);
                builder.setPositiveButton("Cool", null);
                builder.show();

            }
        };

        @Override
        public int getCount() {
            return dataObjects.length;
        }

        @Override
        public Object getItem(int position) {
            return null;
        }

        @Override
        public long getItemId(int position) {
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View retval = LayoutInflater.from(parent.getContext()).inflate(R.layout.viewitem, null);
            TextView title = (TextView) retval.findViewById(R.id.title);
            Button button = (Button) retval.findViewById(R.id.clickbutton);
            button.setOnClickListener(mOnButtonClicked);
            title.setText(dataObjects[position]);

            return retval;
        }

    };

}

我的上面的代码工作正常，它向我显示水平列表视图，但在顶部，我的问题是，如何在底部列表，我自己尝试设置重力底部但不能正常工作。有什么帮助吗？谢谢

Answer 1

而不是linearLayout使用RelativeLayout。

或者将android:gravity="bottom"设置为linearLayout

Answer 2

就像vipul mittal所说的那样，改为使用RelativeLayout，但你不必非常改变。

将您当前的LinearLayout换成RelativeLayout并添加到LinearLayout该属性 android:alignParentBottom="true"并RelativeLayout的高度fill_parent。

我只是摆脱你的LinearLayout并将其替换为RelativeLayout并使用我之前提到的相同属性将视图与父母的底部对齐。

Answer 3

试试这个..

将android:gravity="bottom"设为主LinearLayout并将HorizontalListView 身高设为 100dp ，如android:layout_height="100dp"。

如果没有明确指定身高，则无法将HorizontalListView修复为底部

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#fff"
    android:gravity="bottom"
    android:orientation="vertical" >

    <com.example.horizontallistview_snapit.HorizontalListView
        android:id="@+id/listview"
        android:layout_width="fill_parent"
        android:layout_height="100dp"
        android:layout_gravity="bottom"
        android:background="#ddd" />

</LinearLayout>

Answer 4

我正在为您提供一些如何使用相对Layout的代码。希望这可以帮助您： -

        <RelativeLayout
        android:id="@+id/panel1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
         android:background="#ffffff">

        <Button
            android:id="@+id/btnGalleryFullScreenClose"
            android:layout_width="40dp"
            android:layout_height="40dp"
            android:layout_alignParentLeft="true"
            android:background="@drawable/close"
            android:layout_marginLeft="5dp"
            android:gravity="top" />

        <Button
            android:id="@+id/btnGalleryFullScreenForward"
            android:layout_width="90dp"
            android:layout_height="40dp"
            android:layout_alignParentRight="true"
            android:layout_marginRight="5dp"
            android:background="@drawable/share" />

        <TextView
            android:id="@+id/txtGalleryFullScreenTitle"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@+id/btnGalleryFullScreenClose"
            android:gravity="center_horizontal"
            android:layout_toLeftOf="@+id/btnGalleryFullScreenForward"
            android:text="Hello World"
            android:textColor="#555555"
            android:textSize="24sp" />
    </RelativeLayout>

在底部设置水平列表视图

4 个答案: