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Android 动态添加视图时出现NullPointerException(上下文?)_Android_View_Android Context - Fatal编程技术网

Android 动态添加视图时出现NullPointerException(上下文?)

Android 动态添加视图时出现NullPointerException(上下文?),android,view,android-context,Android,View,Android Context,我正在尝试在另一个版面中的版面中添加和修改一些文本 我试图通过调用下一个方法来实现,但当它试图修改tv\u event\u hour的文本时,它崩溃了 行:tv\u event\u hour.setText(getHour(timestamp)+“-” 有什么问题 public void addInputDescription(int timestamp, String description) { LinearLayout mRootLayout = (LinearLa

我正在尝试在另一个版面中的版面中添加和修改一些文本

我试图通过调用下一个方法来实现,但当它试图修改
tv\u event\u hour
的文本时,它崩溃了

行:
tv\u event\u hour.setText(getHour(timestamp)+“-”

有什么问题

public void addInputDescription(int timestamp, String description)
    {
        LinearLayout mRootLayout = (LinearLayout) findViewById(R.id.event_container);
        LayoutInflater inflater = (LayoutInflater) _c.getSystemService( Context.LAYOUT_INFLATER_SERVICE );
        View mChildView = inflater.inflate(R.layout.program_event_day_header, mRootLayout, false);
        ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
        mRootLayout.addView(mChildView, params);

        TextView tv_event_hour = (TextView) mChildView.findViewById(R.id.tv_event_hour);
        TextView tv_event_message = (TextView) mChildView.findViewById(R.id.tv_event_message);

        tv_event_hour.setText(getHour(timestamp) + " - ");
        tv_event_message.setText(description);
    }

public String getHour(long timeStamp){
    Date df = new Date(timeStamp*1000);
    return new SimpleDateFormat("HH:mm").format(df);
}

您的
program\u event\u day\u header
版面是否有id为
tv\u event\u hour
的视图?NPE的确切堆栈跟踪是什么?你能同时发布getHour吗?你能发布LogCat吗?要么你的版面中没有tv\u event\u hour id,因此你的TextView为空,要么崩溃发生在getHour中。在此行设置断点:TextView tv\u event\u hour=(TextView)mChildView.findView wById(R.id.tv\u event\u hour);执行一步,检查tv\u event\u hour是否为空。很抱歉,我犯了一个错误,我调用了R.layout.program\u event\u day\u头,但正确的XML是R.layout.program\u event\u day\u输入。