Question

我正在尝试在我的应用程序中使用TabHost实现Tabs，但我得到这个空指针异常。下面我有代码。任何人都可以帮助我。

final TabHost tabHost = (TabHost)findViewById(android.R.id.tabhost);

    final TabHost.TabSpec tab1 = tabHost.newTabSpec("First Tab");
    final TabHost.TabSpec tab2 = tabHost.newTabSpec("Second Tab");


    // Set the Tab name and Activity
    // that will be opened when particular Tab will be selected

    tab1.setIndicator("Upcoming Matches").setContent(new Intent(this, ViewOtherExpense.class));
    tab2.setIndicator("Recent Matches").setContent(new Intent(this, viewExpenseTypes.class));

    /** Add the tabs  to the TabHost to display. */
    tabHost.addTab(tab1);
    tabHost.addTab(tab2);
    tabHost.setup();
    tabHost.getTabWidget().getChildAt(0).setBackgroundColor(Color.parseColor("#3399FF")); //selected
    tabHost.getTabWidget().getChildAt(1).setBackgroundColor(Color.parseColor("#ADD6FF")); //unselected
    //To change the Tab color
    tabHost.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
        @Override
        public void onTabChanged(String tabId) {
            // TODO Auto-generated method stub
            for (int i = 0; i < tabHost.getTabWidget().getChildCount(); i++) {
                tabHost.getTabWidget().getChildAt(i).setBackgroundColor(Color.parseColor("#ADD6FF"));//unselected

            }
            tabHost.getTabWidget().getChildAt(tabHost.getCurrentTab()).setBackgroundColor(Color.parseColor("#3399FF")); // selected

        }


    });

Answer 1

如果加载setup()正在使用TabHost，则必须在添加标签之前致电findViewById()。

所以我建议您在初始化之后和之前调用tabHost.setup();之前添加tabHost.addTab()

final TabHost tabHost = (TabHost)findViewById(android.R.id.tabhost);
tabHost.setup();

尝试调用虚方法＆＃39; void android.widget.TabWidget.addView（android.view.View）＆＃39;在空对象引用

1 个答案: