您好我有3个活动，主要活动，包含菜单，我可以在哪里开始另一项活动。 但我只能开始第一项活动。当我想要开始第二个活动时，我的应用程序关闭。使用以下logcat。 我希望这足够了，因为10米的活动有点长。
logcat的：
09-08 18:50:41.185: D/AndroidRuntime(3065): Shutting down VM
09-08 18:50:41.195: W/dalvikvm(3065): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
09-08 18:50:41.285: E/AndroidRuntime(3065): FATAL EXCEPTION: main
09-08 18:50:41.285: E/AndroidRuntime(3065): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.vkedco.mobappdev.draw_touch_drive_00001/org.vkedco.mobappdev.draw_touch_drive_00001.e_10m}: java.lang.ClassCastException: org.vkedco.mobappdev.draw_touch_drive_00001.y_50m cannot be cast to org.vkedco.mobappdev.draw_touch_drive_00001.y_10m
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread.access$600(ActivityThread.java:141)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.os.Handler.dispatchMessage(Handler.java:99)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.os.Looper.loop(Looper.java:137)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread.main(ActivityThread.java:5041)
09-08 18:50:41.285: E/AndroidRuntime(3065): at java.lang.reflect.Method.invokeNative(Native Method)
09-08 18:50:41.285: E/AndroidRuntime(3065): at java.lang.reflect.Method.invoke(Method.java:511)
09-08 18:50:41.285: E/AndroidRuntime(3065): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
09-08 18:50:41.285: E/AndroidRuntime(3065): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
09-08 18:50:41.285: E/AndroidRuntime(3065): at dalvik.system.NativeStart.main(Native Method)
09-08 18:50:41.285: E/AndroidRuntime(3065): Caused by: java.lang.ClassCastException: org.vkedco.mobappdev.draw_touch_drive_00001.y_50m cannot be cast to org.vkedco.mobappdev.draw_touch_drive_00001.y_10m
09-08 18:50:41.285: E/AndroidRuntime(3065): at org.vkedco.mobappdev.draw_touch_drive_00001.e_10m.onCreate(e_10m.java:107)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.Activity.performCreate(Activity.java:5104)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
09-08 18:50:41.285: E/AndroidRuntime(3065): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
09-08 18:50:41.285: E/AndroidRuntime(3065): ... 11 more
09-08 18:50:44.225: I/Process(3065): Sending signal. PID: 3065 SIG: 9
清单：
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="org.vkedco.mobappdev.draw_touch_drive_00001"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="org.vkedco.mobappdev.draw_touch_drive_00001.MainActivity"
android:label="@string/title_activity_draw_touch_drive_main"
android:screenOrientation="portrait" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="org.vkedco.mobappdev.draw_touch_drive_00001.e_50m"
android:label="@string/title_activity_main"
android:screenOrientation="portrait" >
</activity>
<activity
android:name="org.vkedco.mobappdev.draw_touch_drive_00001.e_10m"
android:label="@string/title_activity_rifle_10m" >
</activity>
</application>
</manifest>
MainActivity：
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btnSimple = (Button) findViewById(R.id.e_50m);
btnSimple.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, e_50m.class);
startActivity(intent);
}
});
Button btnSimple2 = (Button) findViewById(R.id.e_10m);
btnSimple2.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, e_10m.class);
startActivity(intent);
}
});
}
}
public class e_10m extends Activity{
public RelativeLayout mContent;
y_10m mTicTacToeView = null;
public static String tempDir;
public File mypath;
public static Bitmap mBitmap;
public static int width;
public static int height;
public static int r = 0;
public static float x;
public static float y;
public static float X;
public static float Y;
public static double vzdalenost;
public String current = null;
private String uniqueId;
publicy_10m mSignature;
public View mView;
static TextView i;
public static int q=0;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.zaznam_ran);
File directory = new File(Environment.getExternalStorageDirectory() + "/e_10m");
if(!directory.exists())
directory.mkdir();
uniqueId = "_" ;
current = uniqueId + ".png";
mypath= new File(directory,current);
mContent = (RelativeLayout) findViewById(R.id.rl);
mSignature = new y_10m(this, null);
mSignature.setBackgroundColor(Color.TRANSPARENT);
mContent.addView(mSignature, LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
mView = mContent;
Display display = getWindowManager().getDefaultDisplay();
width = (display.getWidth());
height = (display.getHeight());
mTicTacToeView = (y_10m) this.findViewById(R.id.pntr);
Button btn3 = (Button) findViewById(R.id.button3);
btn3.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(y_10m.t == 10){
y_10m.Vycistit();
}
y_10m.PridatRanu();
}
});
Button btn4 = (Button) findViewById(R.id.button4);
btn4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
y_10m.krouzkyMazat();
if (q>=1){q = q-1;}
}
});
Button btn5 = (Button) findViewById(R.id.button5);
btn5.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Krouzky_10m.Vycistit();
q=0;
y_10m.t = 0;
}
});
Button btn6 = (Button) findViewById(R.id.button6);
btn6.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.v("log_tag", "Panel Saved");
mView.setDrawingCacheEnabled(true);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
getMenuInflater().inflate(R.menu.activity_draw_touch_drive_main, menu);
return true;
}
@Override
protected void onDestroy() {
super.onDestroy();
if ( mTicTacToeView != null ) {
mTicTacToeView.NemuzemeVykreslovat();
mTicTacToeView = null;
}
}
@Override
public void onLowMemory() {
super.onLowMemory();
if ( mTicTacToeView != null ) {
mTicTacToeView.NemuzemeVykreslovat();
mTicTacToeView = null;
}
}
@Override
protected void onPause() {
super.onPause();
if ( mTicTacToeView != null ) {
mTicTacToeView.NemuzemeVykreslovat();
}
}
@Override
protected void onStart() {
super.onStart();
if ( mTicTacToeView != null ) {
mTicTacToeView.MuzemeVykreslovat();
}
else {
mTicTacToeView = (y_10m) this.findViewById(R.id.pntr);
mTicTacToeView.MuzemeVykreslovat();
}
y_10m.Vycistit();
q=0;
y_10m.t = 0;
}
@Override
protected void onStop() {
super.onStop();
if ( mTicTacToeView != null ) {
mTicTacToeView.NemuzemeVykreslovat();
}
}
}
zaznam_ran中的pntr视图：
<org.vkedco.mobappdev.draw_touch_drive_00001.y_50m
android:id="@+id/pntr"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:tag="Painter" />
答案 0 :(得分：0)
问题在于，在您的代码中，您将y_50m View投射到y_10m View。
下面
mTicTacToeView = (y_10m) this.findViewById(R.id.pntr);
将其替换为
mTicTacToeView = (y_50m) this.findViewById(R.id.pntr);