我正在尝试为我的Android应用程序设计仪表板，并从以下链接获取指导：
http://www.androidhive.info/2011/12/android-dashboard-design-tutorial/
但我面临的问题是图标没有显示出来。我得到一个空白显示，蓝色活动背景颜色设置。但是没有显示仪表板图标。我的代码是这样的：
班级档案：
package kanix.highrise.com.db;
import android.app.Activity;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
public class AndroidDashboardDesignActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dashboard_layout);
/**
* Creating all buttons instances
* */
// Dashboard News feed button
Button btn_newsfeed = (Button) findViewById(R.id.btn_news_feed);
// Dashboard Friends button
Button btn_friends = (Button) findViewById(R.id.btn_friends);
// Dashboard Messages button
Button btn_messages = (Button) findViewById(R.id.btn_messages);
// Dashboard Places button
Button btn_places = (Button) findViewById(R.id.btn_places);
// Dashboard Events button
Button btn_events = (Button) findViewById(R.id.btn_events);
// Dashboard Photos button
Button btn_photos = (Button) findViewById(R.id.btn_photos);
/**
* Handling all button click events
* */
// Listening to News Feed button click
btn_newsfeed.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), NewsFeedActivity.class);
// startActivity(i);
}
});
// Listening Friends button click
btn_friends.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), FriendsActivity.class);
// startActivity(i);
}
});
// Listening Messages button click
btn_messages.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), MessagesActivity.class);
// startActivity(i);
}
});
// Listening to Places button click
btn_places.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), PlacesActivity.class);
// startActivity(i);
}
});
// Listening to Events button click
btn_events.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), EventsActivity.class);
// startActivity(i);
}
});
// Listening to Photos button click
btn_photos.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Launching News Feed Screen
// Intent i = new Intent(getApplicationContext(), PhotosActivity.class);
// startActivity(i);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_android_dashboard_design, menu);
return true;
}
@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.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
另一个班级
package kanix.highrise.com.db;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
/**
* Created by Mubashir.gul on 30/04/2015.
*/
public class DashboardLayout extends ViewGroup {
private static final int UNEVEN_GRID_PENALTY_MULTIPLIER = 10;
private int mMaxChildWidth = 0;
private int mMaxChildHeight = 0;
public DashboardLayout(Context context) {
super(context, null);
}
public DashboardLayout(Context context, AttributeSet attrs) {
super(context, attrs, 0);
}
public DashboardLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
mMaxChildWidth = 0;
mMaxChildHeight = 0;
// Measure once to find the maximum child size.
int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
MeasureSpec.getSize(widthMeasureSpec), MeasureSpec.AT_MOST);
int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
MeasureSpec.getSize(widthMeasureSpec), MeasureSpec.AT_MOST);
final int count = getChildCount();
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
mMaxChildWidth = Math.max(mMaxChildWidth, child.getMeasuredWidth());
mMaxChildHeight = Math.max(mMaxChildHeight, child.getMeasuredHeight());
}
// Measure again for each child to be exactly the same size.
childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
mMaxChildWidth, MeasureSpec.EXACTLY);
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
mMaxChildHeight, MeasureSpec.EXACTLY);
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
}
setMeasuredDimension(
resolveSize(mMaxChildWidth, widthMeasureSpec),
resolveSize(mMaxChildHeight, heightMeasureSpec));
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
int width = r - l;
int height = b - t;
final int count = getChildCount();
// Calculate the number of visible children.
int visibleCount = 0;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
++visibleCount;
}
if (visibleCount == 0) {
return;
}
// Calculate what number of rows and columns will optimize for even horizontal and
// vertical whitespace between items. Start with a 1 x N grid, then try 2 x N, and so on.
int bestSpaceDifference = Integer.MAX_VALUE;
int spaceDifference;
// Horizontal and vertical space between items
int hSpace = 0;
int vSpace = 0;
int cols = 1;
int rows;
while (true) {
rows = (visibleCount - 1) / cols + 1;
hSpace = ((width - mMaxChildWidth * cols) / (cols + 1));
vSpace = ((height - mMaxChildHeight * rows) / (rows + 1));
spaceDifference = Math.abs(vSpace - hSpace);
if (rows * cols != visibleCount) {
spaceDifference *= UNEVEN_GRID_PENALTY_MULTIPLIER;
}
if (spaceDifference < bestSpaceDifference) {
// Found a better whitespace squareness/ratio
bestSpaceDifference = spaceDifference;
// If we found a better whitespace squareness and there's only 1 row, this is
// the best we can do.
if (rows == 1) {
break;
}
} else {
// This is a worse whitespace ratio, use the previous value of cols and exit.
--cols;
rows = (visibleCount - 1) / cols + 1;
hSpace = ((width - mMaxChildWidth * cols) / (cols + 1));
vSpace = ((height - mMaxChildHeight * rows) / (rows + 1));
break;
}
++cols;
}
// Lay out children based on calculated best-fit number of rows and cols.
// If we chose a layout that has negative horizontal or vertical space, force it to zero.
hSpace = Math.max(0, hSpace);
vSpace = Math.max(0, vSpace);
// Re-use width/height variables to be child width/height.
width = (width - hSpace * (cols + 1)) / cols;
height = (height - vSpace * (rows + 1)) / rows;
int left, top;
int col, row;
int visibleIndex = 0;
for (int i = 0; i < count; i++) {
final View child = getChildAt(i);
if (child.getVisibility() == GONE) {
continue;
}
row = visibleIndex / cols;
col = visibleIndex % cols;
left = hSpace * (col + 1) + width * col;
top = vSpace * (row + 1) + height * row;
child.layout(left, top,
(hSpace == 0 && col == cols - 1) ? r : (left + width),
(vSpace == 0 && row == rows - 1) ? b : (top + height));
++visibleIndex;
}
}
}
我的xml文件是这样的：
actionbar_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent" style="@style/ActionBarCompat"
>
<ImageView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:clickable="false"
android:paddingLeft="15dip"
android:scaleType="center"
/>
/>
</LinearLayout>
dashboard_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/home_root"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- Include Action Bar -->
<include layout="@layout/actionbar_layout"/>
<!-- Include Fragmented dashboard -->
<include layout="@layout/fragment_layout"/>
<!-- Include Footer -->
<include layout="@layout/footer_layout"/>
</LinearLayout>
fragment_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<kanix.highrise.com.db.DashboardLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<Button
android:id="@+id/btn_news_feed"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="News Feed" />
<!-- Friends Button -->
<Button
android:id="@+id/btn_friends"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="Friends"
android:textColor="#fff"/>
<!-- Messages Button -->
<Button
android:id="@+id/btn_messages"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="Messages" />
<!-- Places Button -->
<Button
android:id="@+id/btn_places"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="Places" />
<!-- Events Button -->
<Button
android:id="@+id/btn_events"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="Events" />
<!-- Photos Button -->
<Button
android:id="@+id/btn_photos"
style="@style/DashboardButton"
android:drawableTop="@mipmap/works"
android:text="Photos" />
</kanix.highrise.com.db.DashboardLayout>
footer_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent" style="@style/FooterBar" >
<TextView android:text="www.facebook.com"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textColor="#606060"
android:gravity="center"
android:paddingTop="10dip"/>
</LinearLayout>
我的Styles.xml文件是这样的：
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="ActionBarCompat">
<item name="android:layout_width">fill_parent</item>
<item name="android:layout_height">50dp</item>
<item name="android:orientation">horizontal</item>
<item name="android:background">#2E5EA3</item>
</style>
<style name="DashboardButton">
<item name="android:layout_gravity">center_vertical</item>
<item name="android:layout_width">wrap_content</item>
<item name="android:layout_height">wrap_content</item>
<item name="android:gravity">center_horizontal</item>
<item name="android:drawablePadding">2dp</item>
<item name="android:textSize">16dp</item>
<item name="android:textStyle">bold</item>
<item name="android:textColor">#fff</item>
<item name="android:background">@null</item>
</style>
<style name="FooterBar">
<item name="android:layout_width">fill_parent</item>
<item name="android:layout_height">40dp</item>
<item name="android:orientation">horizontal</item>
<item name="android:background">#dedede</item>
</style>
</resources>
我不知道我做错了哪里尝试了很多东西。我也在所有图标上使用相同的图像。
答案 0 :(得分：1)
图标未显示，因为您可能无法将图像保留在可绘制文件夹中。
请参阅android:drawableTop="@drawable/btn_newsfeed"此代码表示会有＆＃34; newsfeed＆＃34;图标，文字上方＆＃34;新闻Feed＆＃34;。
您必须将图像文件保存在名为btn_newsfeed的可绘制文件夹中，对于其他Button图像也是如此。
<Button
android:id="@+id/btn_news_feed"
style="@style/DashboardButton"
android:drawableTop="@drawable/btn_newsfeed"
android:text="News Feed" />
希望这会对你有所帮助，如果不清楚，你可以发表评论并提问。