我使用tabHost在我的应用程序中创建了4个选项卡,它运行正常。 当我点击我的第一个标签时,它将加载相应的xml页面并显示一些细节。在该页面中有一个按钮,当我点击该按钮时,它将使用Intent加载另一个活动。我的问题是如何在同一个标签中显示该活动?
答案 0 :(得分:4)
您必须使用此课程
import java.util.ArrayList;
import android.app.Activity;
import android.app.ActivityGroup;
import android.app.LocalActivityManager;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Window;
public class TabActivityGroup extends ActivityGroup {
private ArrayList<String> mIdList;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (mIdList == null)
mIdList = new ArrayList<String>();
}
/**
* This is called when a child activity of this one calls its finish method.
* This implementation calls {@link LocalActivityManager#destroyActivity} on
* the child activity and starts the previous activity. If the last child
* activity just called finish(),this activity (the parent), calls finish to
* finish the entire group.
*/
@Override
public void finishFromChild(Activity child) {
LocalActivityManager manager = getLocalActivityManager();
int index = mIdList.size() - 1;
if (index < 1) {
finish();
return;
}
manager.destroyActivity(mIdList.get(index), true);
mIdList.remove(index);
index--;
String lastId = mIdList.get(index);
Intent lastIntent = manager.getActivity(lastId).getIntent();
Window newWindow = manager.startActivity(lastId, lastIntent);
setContentView(newWindow.getDecorView());
}
/**
* Starts an Activity as a child Activity to this.
*
* @param Id
* Unique identifier of the activity to be started.
* @param intent
* The Intent describing the activity to be started.
* @throws android.content.ActivityNotFoundException.
*/
public void startChildActivity(String Id, Intent intent) {
Window window = getLocalActivityManager().startActivity(Id,
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP));
if (window != null) {
mIdList.add(Id);
setContentView(window.getDecorView());
}
}
/**
* The primary purpose is to prevent systems before
* android.os.Build.VERSION_CODES.ECLAIR from calling their default
* KeyEvent.KEYCODE_BACK during onKeyDown.
*/
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
// preventing default implementation previous to
// android.os.Build.VERSION_CODES.ECLAIR
return true;
}
return super.onKeyDown(keyCode, event);
}
/**
* Overrides the default implementation for KeyEvent.KEYCODE_BACK so that
* all systems call onBackPressed().
*/
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
onBackPressed();
return true;
}
return super.onKeyUp(keyCode, event);
}
/**
* If a Child Activity handles KeyEvent.KEYCODE_BACK. Simply override and
* add this method.
*/
@Override
public void onBackPressed() {
int length = mIdList.size();
if (length > 1) {
Activity current = getLocalActivityManager().getActivity(
mIdList.get(length - 1));
current.finish();
}
}
}
将此课程扩展为另一项活动,如下所示
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
public class InterMediateActivity extends TabActivityGroup{
String TabID;
String TabName;
@Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
TabID=getIntent().getStringExtra("TabID");
TabName=getIntent().getStringExtra("TabName");
Log.i("Tab from intermediate",""+TabID+" "+TabName);
filterTabs(TabID);
}
private void filterTabs(String TabID)
{
startChildActivity("Options", new Intent(this,HomePage.class));
}
}
而不是直接从标签中调用内部活动,首先导航到InterMediateActivity
如下所示
Intent intent = new Intent(this, InterMediateActivity.class);
intent.putExtra("TabID", item.elementAt(0));
intent.putExtra("TabName", item.elementAt(1));
specTab.setContent(intent);
mTabHost.addTab(specTab);