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Android 致命的例外:你能帮我吗?_Android - Fatal编程技术网

Android 致命的例外:你能帮我吗?

Android 致命的例外:你能帮我吗?,android,Android,我想添加标签到内容主!我的代码有问题!这是我的XML代码,用于content_main!错误消息显示: }> 以及TabActivityLayout代码: public class TabActivityLayout extends TabActivity { private TabHost mTabHost; @Override public void onCreate(Bundle SavedInstanceState){ super.onCreat

我想添加标签到内容主!我的代码有问题!这是我的XML代码,用于content_main!错误消息显示:

}> 以及TabActivityLayout代码:

    public class TabActivityLayout extends TabActivity {
    private TabHost mTabHost;
    @Override
    public void onCreate(Bundle SavedInstanceState){
    super.onCreate(SavedInstanceState);
    setContentView(R.layout.content_main);
    mTabHost =getTabHost();
    TabHost.TabSpec spec;
    Intent intent;

    // Francai sTab
    intent = new Intent(this,FrancaisActivity.class);
     spec =mTabHost.newTabSpec("Francais")
             .setIndicator("Francais")
             .setContent(intent);

    // Anglais Tab
            intent = new Intent(this,AnglaisActivity.class);
    spec =mTabHost.newTabSpec("Anglais")
            .setIndicator("Anglais")
            .setContent(intent);
    mTabHost.addTab(spec);

    // Arabe Tab
            intent = new Intent(this,ArabeActivity.class);
    spec =mTabHost.newTabSpec("Arabe")
            .setIndicator("Arabe")
            .setContent(intent);
    mTabHost.addTab(spec);

   mTabHost.setCurrentTab(2);

}

}以下代码正在引发致命异常:

TabActivityLayout tabActivityLayout=new TabActivityLayout();
tabActivityLayout.setContentView(R.layout.content_main);
您不应该从另一个活动设置contentView,
setContentView()
将在活动
onCreate()
方法中调用

还有一个建议,下面的一行重复了3次:

DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
如果需要在onCreate()之外访问该视图,则需要将其声明为字段:

private DrawerLayout drawer;
然后将其设置为仅初始化一次,就在
setContentView()之后。
就像您对另一个视图所做的那样:

drawer = (DrawerLayout) findViewById(R.id.drawer_layout);

请发布异常+完整堆栈跟踪+触发的行不会成为任何异常的原因,是吗?“如果您需要在onCreate()之外访问该视图,则需要将其声明为字段”是不正确的。@weston您有一个正确的观点,我只是想提供帮助,只是在我的答案上进行了扩展
private DrawerLayout drawer;
drawer = (DrawerLayout) findViewById(R.id.drawer_layout);