使用标签Android通过XML调用onClick答案

【问题标题】：Calling onClick through XML using tags Android使用标签Android通过XML调用onClick
【发布时间】：2014-03-18 06:29:05
【问题描述】：

我正在创建一个简单的绘图应用程序，它通过我的布局文件中的android:onClick="changeColor" 的图像按钮在我的主要活动中调用changeColor() 方法。我的主要线性布局和通过对话框显示的布局中有图像按钮。这两种布局具有相同的图像按钮代码，但是当我尝试通过对话框中的布局 XML 文件更改颜色时，它崩溃了。我得到的错误说它找不到changeColor() 方法。解决我的错误的最佳方法是什么。

MainActivity.java

public class MainActivity extends ActionBarActivity implements OnClickListener {
private PaintView pView;
private ImageButton currentColor;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    pView = (PaintView) findViewById(R.id.drawing);
    LinearLayout paintLayout = (LinearLayout) findViewById(R.id.paint_colors);
    currentColor = (ImageButton) paintLayout.getChildAt(0);
    currentColor.setImageDrawable(getResources().getDrawable(
            R.drawable.paint_pressed));

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {

    super.onCreateOptionsMenu(menu);
    MenuInflater menuInflater = getMenuInflater();
    menuInflater.inflate(R.menu.main, 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.
    switch (item.getItemId()) {
    case R.id.color:
        Toast.makeText(getApplicationContext(), "edit selected",
                Toast.LENGTH_SHORT).show();

        Dialog brushColorDialog = new Dialog(this);
        brushColorDialog.setTitle("Brush Color:");
        brushColorDialog.setContentView(R.layout.colors);
        brushColorDialog.show();
        return true;
    case R.id.brush:
        Dialog brushSizeDialog = new Dialog(this);
        brushSizeDialog.setTitle("Brush Size:");
        brushSizeDialog.setContentView(R.layout.brush_chooser);
        Toast.makeText(getApplicationContext(), "Brush Dialog goes here",
                Toast.LENGTH_SHORT).show();
        brushSizeDialog.show();
        return true;
    default:
        return super.onOptionsItemSelected(item);
    }

}

public void changeColor(View view) {
    // use chosen color
    if (view != currentColor) {
        // update color
        ImageButton imgView = (ImageButton) view;
        String color = view.getTag().toString();
        pView.setColor(color);
        imgView.setImageDrawable(getResources().getDrawable(
                R.drawable.paint_pressed));
        currentColor.setImageDrawable(getResources().getDrawable(
                R.drawable.paint));
        currentColor = (ImageButton) view;
    }
}

@Override
public void onClick(View v) {
    // TODO Auto-generated method stub

}

}

colors.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
 android:layout_height="400dp"
 android:gravity="center"
 android:orientation="vertical" >


<LinearLayout
    android:id="@+id/paint_colors"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FFFF0000"
        android:contentDescription="@string/paint"
        android:onClick=""
        android:src="@drawable/paint"
        android:tag="#FFFF0000" />

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FF800000"
        android:contentDescription="@string/paint"
        android:onClick="changeColor"
        android:src="@drawable/paint"
        android:tag="#FF800000" />

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FFFFFF00"
        android:contentDescription="@string/paint"
        android:onClick="changeColor"
        android:src="@drawable/paint"
        android:tag="#FFFFFF00" />

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FF808000"
        android:contentDescription="@string/paint"
        android:onClick="changeColor"
        android:src="@drawable/paint"
        android:tag="#FF808000" />
</LinearLayout>
<!-- Bottom Row -->

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FF00FF00"
        android:contentDescription="@string/paint"
        android:onClick="changeColor"
        android:src="@drawable/paint"
        android:tag="#FF00FF00" />

    <ImageButton
        android:layout_width="@dimen/large_tile"
        android:layout_height="@dimen/large_tile"
        android:layout_margin="0dp"
        android:background="#FF008000"
        android:contentDescription="@string/paint"
        android:onClick="changeColor"
        android:src="@drawable/paint"
        android:tag="#FF008000" />

activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FFCCCCCC"
android:orientation="vertical"
tools:context=".MainActivity" >

<net.soloq.paint4.PaintView
android:id="@+id/drawing"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_marginBottom="3dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:layout_marginTop="3dp"
android:layout_weight="1"
android:background="#FFFFFFFF" />
<!-- Top Row -->
<LinearLayout
android:id="@+id/paint_colors"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal" >
   <ImageButton
android:layout_width="@dimen/large_brush"
android:layout_height="@dimen/large_brush"
android:layout_margin="2dp"
android:background="#FF660000"
android:contentDescription="@string/paint"
android:onClick="changeColor"
android:src="@drawable/paint"
android:tag="#FF660000" />

<ImageButton
android:layout_width="@dimen/large_brush"
android:layout_height="@dimen/large_brush"
android:layout_margin="2dp"
android:background="#FFFF0000"
android:contentDescription="@string/paint"
android:onClick="changeColor"
android:src="@drawable/paint"
android:tag="#FFFF0000" />

activity_main.xml 中的图像按钮工作正常，但在 colors.xml 上崩溃

提前致谢！

【问题讨论】：

请张贴您的日志猫。而你错过了break 声明
03-18 01:44:54.031: E/AndroidRuntime(17948): FATAL EXCEPTION: main 03-18 01:44:54.031: E/AndroidRuntime(17948): Process: net.soloq.paint4, PID: 17948 03-18 01:44:54.031: E/AndroidRuntime(17948): java.lang.IllegalStateException: Could not find a method changeColor(View) in the activity class android.view.ContextThemeWrapper for onClick handler on view class android.widget.ImageButton 03-18 01:44:54.031: E/AndroidRuntime(17948): at android.view.View$1.onClick(View.java:3817) 03-18 01:44:54.031: E/AndroidRuntime(17948): at android.view.View.performClick(View.java:4445)

标签： java android xml android-layout

【解决方案1】：

从colors.xml中删除这一行...

android:onClick="changeColor"

并将id 添加到ImageButton XML 如下...

<ImageButton
    android:id="@+id/colorImageButton"
    android:layout_width="@dimen/large_tile"
    android:layout_height="@dimen/large_tile"
    android:layout_margin="0dp"
    android:background="#FF800000"
    android:contentDescription="@string/paint"
    android:src="@drawable/paint"
    android:tag="#FF800000" />

然后，如下设置OnClickListener...

 Dialog brushColorDialog = new Dialog(this);
 brushColorDialog.setTitle("Brush Color:");
 brushColorDialog.setContentView(R.layout.colors);

 ImageButton imageBtn = (ImageButton)brushColorDialog.findViewById(R.id.colorImageButton);
 imageBtn.setOnClickListener(new OnClickListener(){
     @Override
     public void onClick(View v) {
         //add your code here
     }
 });

 brushColorDialog.show();

【讨论】：

我目前有 16 个按钮。是否有一种简单的方法可以做到这一点而不必为每个按钮都这样做？

【解决方案2】：

我遇到了同样的问题，如果我没记错的话，问题出在清单中，主题引用导致应用程序搜索主题中的点击代表。搜索主题引用并删除它（如果存在）。

【讨论】：