Question

我正在开发一个具有文本消息界面的应用程序（例如Facebook Messenger，Whatsapp等）。我希望能够更改用户在df %>% filter( (str_detect(id, "^M.+(KIT|FLEECE)") & between(f1, 300, 400) & between(f2, 1300, 1400)) | (str_detect(id, "^M.+(GOOSE)") & between(f1, 200, 350) & between(f2, 1200, 1400)) )中选择新颜色时发送的所有聊天气泡（ListView中的TextView个）的背景颜色。

但是，使用当前的代码，仅在再次单击用于撰写邮件的NavigationView后才能更改颜色。或者，我只能编辑发送的第一个气泡，但是一旦颜色更改即可。

这就是我尝试过的：

EditText

ItemColor1.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v){ Toast.makeText(activity, "Couleur mise à jour", Toast.LENGTH_SHORT).show(); currentTheme = position; SharedPreferences.Editor editor = pref.edit(); editor.putInt("indexColorSelected",currentTheme); editor.apply(); chatAdapter.notifyDataSetChanged(); //the following changes only the first message sent for(int i=0; i<chatAdapter.getCount(); i++){ ChatData message = chatMessageList.get(position); TextView msg = activity.findViewById(R.id.text); msg.setText(message.body); msg.setBackgroundResource(R.drawable.user_color1); } } });是我创建的一个自定义类，如下所示：

ChatData

可绘制颜色：

public class ChatAdapter extends BaseAdapter {

    private static LayoutInflater inflater = null;
    private ArrayList<ChatData> chatMessageList;
    private Context mContext;

    ChatAdapter(Activity activity, ArrayList<ChatData> list) {
        mContext = activity;
        chatMessageList = list;
        inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }
    ...
}

适配器的

<corners android:bottomRightRadius="5dp" android:radius="40dp"/> <gradient android:angle="45" android:endColor="#01f1fa" android:startColor="#0189ff" android:type="linear" /> </shape>方法：

getView()

我真的不知道从这里去哪里，所以我们将不胜感激。如果您希望我提供更多代码，请告诉我，我会的。

谢谢。

Answer 1

我正在分享我将如何做。也许可以帮到您。有一个奇怪的问题，因为您正在呼叫notifyDataSetChanged()。这足以重新绘制所有消息气泡。

我的想法是：

向适配器类（int）添加mColorResource变量。此变量将指向应使用的适当可绘制对象（例如R.drawable.user_color1）。

public class ChatAdapter extends BaseAdapter {

    int mColorResource;

    ChatAdapter(Activity activity, ArrayList<ChatData> list, int initialColorResource) {
        mContext = activity;
        chatMessageList = list;
        inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        // You must receive the color on the construtor
        mColorResource = initialColor;
    }

    // Use this method to update the color (when user select a new color)
    public void setColor(int newColorResource) {
        mColorResource = newColorResource;
    }


    public View getView(int position, View convertView, ViewGroup parent) {
        ...
        // Note how this if-else is cleaner now
        if (message.isMine) {
            layout.setGravity(Gravity.RIGHT);
            msg.setBackgroundResource(mColorResource);
            parent_layout.setGravity(Gravity.RIGHT);
        } else {
            layout.setGravity(Gravity.LEFT);
            msg.setBackgroundResource(R.drawable.bot_chat);
            parent_layout.setGravity(Gravity.LEFT);
        }
        ...
    }
}

然后，当选择一种颜色时，根据单击的视图找到合适的可绘制对象并将其传递给适配器：

ItemColor1.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v){
        Toast.makeText(activity, "Couleur mise à jour", Toast.LENGTH_SHORT).show();
        currentTheme = position;

        SharedPreferences.Editor editor = pref.edit();
        editor.putInt("indexColorSelected", currentTheme);
        editor.apply();

        // Here, you send the proper drawable...
        // I'm not sure how you convert color selected to the drawable
        // So, add your logic to convert the button clicked to a drawable here
        // like R.drawable.user_color1
        chatAdapter.setColor(R.drawable.NAME_OF_THE_COLOR);

        // Request to re-draw all items from the list (all bubbles)
        chatAdapter.notifyDataSetChanged();
    }
});

此外，在您的活动中，还使用最后使用的颜色创建适配器。像这样：

@Override
protected void onCreate(@Nullable final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ....
    // Set a default color (if user is open you app for the first time)
    int chatColor = R.drawable.user_color1;

    // Add your logic to read the shared preference and convert that last color used to a valid drawable.
    // Like chatColor = pref.getInt(indexColorSelected, R.drawable.user_color1) etc....

    // Set the color in the adapter.
    chatAdapter = newAdapter(this, mChatDataList, chatColor);
}

如何更改ListView中每个项目的背景颜色？

1 个答案: