Android 自定义 Toast 消息在单独的 class 中不起作用

Android Custom Toast Message not working in a separate class

我为自定义 toast 创建了以下方法。

public void customToastMessage(String message){
    LayoutInflater inf = (LayoutInflater)con.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View layout = inf.inflate(R.layout.custom_toast_layout,(ViewGroup)findViewById(R.id.myCustomToast));
    TextView toastMessage = layout.findViewById(R.id.myCustomToastText);
    toastMessage.setText(message);
    Toast warningMessage = Toast.makeText(con, message, Toast.LENGTH_LONG);
    warningMessage.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL, 0, 10);
    warningMessage.setView(layout);
    warningMessage.show();
}

只要这个方法存在于 MainActivity 中,它就可以正常工作,但是当我将它移到一个单独的 class 时,我得到:

"java.lang.IllegalStateException: Could not execute method for android:onClick at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:389)".

下面的 class 我需要更改什么?

public class MyCustomUI extends AppCompatActivity {

    private static Context con;

    public MyCustomUI(Context con){
        this.con = con;
    }

    public void customToastMessage(String message){
         LayoutInflater inf = (LayoutInflater)con.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
         View layout = inf.inflate(R.layout.custom_toast_layout,(ViewGroup)findViewById(R.id.myCustomToast));
         TextView toastMessage = layout.findViewById(R.id.myCustomToastText);
         toastMessage.setText(message);
         Toast warningMessage = Toast.makeText(con, message, Toast.LENGTH_LONG);
         warningMessage.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL, 0, 10);
         warningMessage.setView(layout);
         warningMessage.show();
    }
}

我猜你的问题是当你膨胀你的布局时:

View layout = inf.inflate(R.layout.custom_toast_layout,(ViewGroup)findViewById(R.id.myCustomToast));

我也猜测问题是 (ViewGroup)findViewById(R.id.myCustomToast)。您正在尝试寻找一个 View/ViewGroup,它不存在于 class 上,但存在于您的 MainActivity 上。

将其作为参数传递给您的方法(只是相关部分):

public void customToastMessage(String message, ViewGroup customToast){
    LayoutInflater inf = (LayoutInflater)con.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View layout = inf.inflate(R.layout.custom_toast_layout, viewgroup);