以下所有代码都可以正常运行。也就是说，直到我尝试将第二个onClickListener添加到另一个图像。我试图添加的代码，以及我尝试添加它的位置在下面的代码中列为注释。有没有人看到我在这里遗失的任何东西？我觉得这个额外的实现应该没有任何问题。
公共类MainActivity扩展了Activity {
ImageView mImage;
//ImageView journal;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mImage = (ImageView)MainActivity.this.findViewById(R.id.Floaterimg);
//journal = (ImageView)MainActivity.this.findViewById(R.id.journbtn);
//journal.setOnClickListener(new View.OnClickListener() {
//@Override
//public void onClick (View v) {
//Intent i = new Intent(MainActivity.this,
//SecondActivity.class);
//startActivity(i);
//}
//});
final Handler randomizer = new Handler();
final Runnable rrandomizer = new Runnable() {
public void run() {
RelativeLayout.LayoutParams params = new
LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT);
params.topMargin = (int)(Math.random()*2000 + 1);
params.leftMargin = (int)(Math.random()*3000 + 1);
mImage.setLayoutParams(params);
randomizer.postDelayed(this, 5000);
}
};
rrandomizer.run();
mImage.setOnClickListener(new View.OnClickListener() {
int numClicks = 0;
@Override
public void onClick(View arg0) {
numClicks++;
if(numClicks > 5) {
Bitmap bitmap =
BitmapFactory.decodeResource(getResources(),
R.drawable.ic_launcher);
ByteArrayOutputStream baos = new
ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
byte[] b = baos.toByteArray();
Intent intent = new Intent(MainActivity.this,
SecondActivity.class);
intent.putExtra("picture", b);
}
}
});
}
};
编辑：
按下按钮后来自logcat的错误：
10-18 14:17:32.529: E/InputDispatcher(17677): Event_report_payload: Failed to write keypress event to kernel, error = 5
10-18 14:17:32.529: E/dhcpcd(7483): open_udp_socket: No such device
10-18 14:17:32.549: E/dhcpcd(7483): open_socket: No such file or directory
10-18 14:17:32.549: E/dhcpcd(7483): send_raw_packet: No such file or directory
10-18 14:17:32.609: E/InputDispatcher(17677): Event_report_payload: Failed to write keypress event to kernel, error = 5
10-18 14:17:32.759: E/AndroidRuntime(26780): Uncaught handler: thread main exiting due to uncaught exception
10-18 14:17:32.759: E/Monkey(26780): exception :java.io.FileNotFoundException: /dev/kmsg (Permission denied)
10-18 14:17:32.809: E/AndroidRuntime(26780): exception :java.io.FileNotFoundException: /dev/kmsg (Permission denied)
10-18 14:17:32.809: E/AndroidRuntime(26780): FATAL EXCEPTION: main
10-18 14:17:32.809: E/AndroidRuntime(26780): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.test/com.example.test.SecondActivity}: java.lang.NullPointerException
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1664)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1680)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:945)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.os.Handler.dispatchMessage(Handler.java:99)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.os.Looper.loop(Looper.java:130)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread.main(ActivityThread.java:3719)
10-18 14:17:32.809: E/AndroidRuntime(26780): at java.lang.reflect.Method.invokeNative(Native Method)
10-18 14:17:32.809: E/AndroidRuntime(26780): at java.lang.reflect.Method.invoke(Method.java:507)
10-18 14:17:32.809: E/AndroidRuntime(26780): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:895)
10-18 14:17:32.809: E/AndroidRuntime(26780): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:653)
10-18 14:17:32.809: E/AndroidRuntime(26780): at dalvik.system.NativeStart.main(Native Method)
10-18 14:17:32.809: E/AndroidRuntime(26780): Caused by: java.lang.NullPointerException
10-18 14:17:32.809: E/AndroidRuntime(26780): at com.example.inkuesttest.SecondActivity.onCreate(SecondActivity.java:18)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-18 14:17:32.809: E/AndroidRuntime(26780): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1628)
10-18 14:17:32.809: E/AndroidRuntime(26780): ... 11 more
10-18 14:17:32.829: E/AndroidRuntime(26780): exception :java.io.FileNotFoundException: /dev/kmsg (Permission denied)
10-18 14:17:32.869: E/ActivityManager(17677): set systemprop back to original value~
编辑：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
Bundle extras = getIntent().getExtras();
//line18
byte[] b = extras.getByteArray("picture");
//end line18
Bitmap bmp = BitmapFactory.decodeByteArray(b, 0, b.length);
ImageView image = (ImageView) findViewById(R.id.imageView1);
image.setImageBitmap(bmp);
}
}
答案 0 :(得分：1)
您的问题是，您正试图访问extras中的Intent，但您没有通过任何Intent。您可以在下面的intent.putExtra("picture", b);
中进行操作
onClick()但您不会在其他extras中执行此操作。您要么确保发送null，要么安全SecondActivity检查 Bundle extras = getIntent().getExtras();
//line18
if (getIntent().getExtras() != null)
{
byte[] b = extras.getByteArray("picture");
}
中的内容
null当然，如果是Button，你需要处理下面的行。
修改
如果两个switch通常会做同样的事情，那么你可以See this answer对两者使用相同的方法。然后，您只需id View @Override
public void onClick(View v) { // arg0 is an ugly name for a param so I changed it to v
switch (v.getId())
{
case (R.id.Floaterimg):
// do stuff if this image is clicked;
break;
case (R.id.journbtn):
// do stuff if this image is clicked;
break;
}
}
上Intent，根据点击的内容使用不同的代码。像
switch然后将诸如{{1}}之类的公共代码放在{{1}}语句之外。