我有一个有两个标签的项目。选项卡在主类中创建。这里我也添加了缩放者,以处理选项卡之间的更改。这是一个选项卡的即时:

TabHost tabHost = getTabHost();    
tabHost.setOnTabChangedListener(this);
    TabHost.TabSpec spec;
    Intent intent;
    intent = new Intent().setClass(this, Tab1.class);
    spec = tabHost.newTabSpec("tab1").setIndicator("",
                    res.getDrawable(R.drawable.ic_tab_tab1))
                    .setContent(intent);
            tabHost.addTab(spec);
.

侦听器方法:

public void onTabChanged(String tabName) {
    if (tabName.equals("tab1")){
        tab1.load();
    }
}
.

和类似的第二个标签。我的问题是,如果onCreate()方法只在Tab1和Tab2类中运行一次,我如何在选项卡更改后“强制”主类以显示相应的活动?我收到nullpointerexception

选项卡类是如此:

    public class Tab1 extends Activity{
      public void onCreate(Bundle icicle) {
          super.onCreate(icicle);
          setContentView(R.layout.tab1);
          load();
      }
      public void load(){
        //....
      }
    }
.

有帮助吗?

解决方案

onCreate() method calls only once when your Activity first time loaded.

If you want to perform any functionality on each time you view your Activity, put that functionality in onResume() method.

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