我有一个小问题,一个Android自定义对话框。
I have a little problem with an android custom dialog.
我在onCreateDialog(INT)函数构造一个自定义对话框:
I construct a custom dialog in the onCreateDialog(int) function:
dialog = new Dialog(this);
dialog.setContentView(R.layout.custom_dialog);
dialog.setTitle("Custom Dialog");
我在同一类的onClick(视图)功能:
I have a onClick(View) function in the same class:
public void onClick(View v) {
switch(v.getId()) {
case R.id.dialog_button:
Log.i("pma57","dialog button pressed");
break;
case R.id.main_button:
showDialog(DIALOG_CUSTOM);
break;
}
}
这是XML定义:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:paddingBottom="20dp">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/enter_username" />
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<Button
android:id="@+id/dialog_button"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="OK"
android:onClick="onClick" />
</LinearLayout>
对话框显示出来。但按钮不起作用(应用程序crashs) - 这是相当好的,因为onClick的函数回调的定义在我的主要活动 - 和对话是一个新的活动(?我是正确的)
The Dialog shows up. But the Button does not work (the app crashs)- which is quite ok because the onClick-function for the callback is defined in my main activity - and the dialog is a new activity (am I right?).
不过,我真的不知道我是如何在对话框中实现一个按钮 - 我想这是工艺的基本认识问题。在很长的路将是子类对话框,写那里的一切 - 但有另一种方式,我不看
But I realy don't know how i implement a button in the dialog - I think this is a fundamental understanding problem of the technic. The long way would be to subclass Dialog and write everything there - but is there another way which I don't see?
的捷径可走的,我使用,而不是一个开关组是使用onClickListeners的按钮:
The way round it that I use, rather than having a switch block is to use onClickListeners for the buttons:
dialog = new Dialog(this);
dialog.setContentView(R.layout.custom_dialog);
dialog.setTitle("Custom Dialog");
Button dialog_btn = (Button) dialog.findViewById(R.id.dialog_button);
dialog_btn.setOnClickListener(new View.OnClickListener()
{
// Perform button logic
}
请注意,您是从对话框中找到的观点,而不仅仅是打电话直findViewById因为这将返回一个空指针,因为将在应用程序视图中不dialog_button。
Note that you are finding the view from the dialog, not just calling straight to findViewById as that would return a null pointer as there would be not dialog_button on the application view.