在活动A中,它有listView和一个图标,用于意图活动B.
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() { //listview
public void onItemClick(AdapterView<?> listView, View view, final int position, long id) {
Expenses o = (Expenses) obj.getItem(position);
Uri image = o.getImage();
Intent intent = new Intent(QuickExpenses.this,AddExpenses.class);
intent.putExtra("image",image.toString());
startActivity(intent);
}
});
@Override
public boolean onOptionsItemSelected(MenuItem item) { // get action bar icon
switch (item.getItemId()) {
case R.id.action_add_task:
mClickedPosition = -1;
Intent intent = new Intent(QuickExpenses.this, AddExpenses.class);
startActivityForResult(intent, PROJECT_REQUEST_CODE);
return true;
}
}
活动B
if(getIntent().getExtras()!=null) { //if has value pass from A
Uri imageUri=Uri.parse(getIntent().getStringExtra("image"));
if(imageUri!=null) {
imageView.setImageURI(imageUri);
}
else {
Toast.makeText(getApplication(),"null",Toast.LENGTH_SHORT).show();
}
}
日志
12-22 01:26:12.217 25588-25588/com.example.tony.monthlyexpenses E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.tony.monthlyexpenses/com.example.tony.monthlyexpenses.AddExpenses}: java.lang.NullPointerException: uriString
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2372)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424)
at android.app.ActivityThread.access$600(ActivityThread.java:169)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1388)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5433)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:924)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:691)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException: uriString
我按下listview,一切似乎都很好,我可以看到图像显示在imageview中,但是当我点击图标时,应用程序崩溃了。我添加了if(imageUri!=null)
但它仍然崩溃了。为什么会这样?
我遵循此https://stackoverflow.com/a/25171292/5156075
错误指向Uri imageUri=Uri.parse(getIntent().getStringExtra("image"));
答案 0 :(得分:2)
更新支票。您正在尝试解析可以为null的String,因此在将其解析为uri之前,请检查空值。
String image = getIntent().getExtras().getString("image");
if(image!= null) {
Uri imageUri=Uri.parse(image);
}