覆盖longClick()上的默认行为

时间:2013-09-21 08:12:01

标签: android textview onlongclicklistener

我有TextView。当长按它时,应突出显示完成长按的文本,并且应该出现一个上下文操作菜单,它提供了一些额外的选项。

但是,如果文本突出显示,则上下文操作菜单与所需内容不同。另一方面,如果显示了所需的上下文操作菜单,则不突出显示该文本。

我已将其归零到returnonLongClick函数中的onLongClickListener语句。具体来说,如果onLongClick函数returns true(消耗点击),则会显示上下文操作菜单,但由于长按不会传递给文本选择工具,因此不会激活它。但是,如果onLongClick函数返回false,则会将单击传递给一个函数,该函数会触发copy + paste带有选择的文本的默认行为。

代码:

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.ActionMode;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;

public class HelloTxtView extends Activity {

    //private EditText ed;
    private TextView ed;

    //actionmode callback.
    private ActionMode mActionMode;
    private ActionMode.Callback mActionModeCallback;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_hello_txt_view);

        ed = (TextView) findViewById(R.id.txtview);
        ed.setFocusable(true);
        ed.setText("Hello World! Let's select some text!!");

        initActionModeCallbacks();

        ed.setOnLongClickListener(new View.OnLongClickListener() {

            @Override
            public boolean onLongClick(View v) {
                Log.v(this.toString(), "Long click.");
                ed.setCursorVisible(true);

                Log.v(this.toString(), "Starting actionmodecallback.");
                mActionMode = HelloTxtView.this.startActionMode(mActionModeCallback);
                v.setSelected(true);

                return false;
            }
        });
    }

    public void initActionModeCallbacks() {

        /*
         * This function initializes the callbacks.
         */

        mActionModeCallback = new ActionMode.Callback() {

            @Override
            public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
                //nothing to do here.
                Log.v(this.toString(), "Preparing action mode.");
                return false;
            }

            @Override
            public void onDestroyActionMode(ActionMode mode) {
                Log.v(this.toString(), "Destroy action mode.");
                //mActionModeCallback = null;
            }

            @Override
            public boolean onCreateActionMode(ActionMode mode, Menu menu) {
                Log.v(this.toString(), "Creating new action mode menu.");
                //inflate a new menu.
                MenuInflater inflater = mode.getMenuInflater();
                inflater.inflate(R.menu.options_menu, menu);
                Log.v(this.toString(), "Done inflating menu.");
                return true;
            }

            @Override
            public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
                Log.v(this.toString(), "An item was clicked.");
                switch(item.getItemId()) {
                case R.id.dictLookup:
                    Log.v(this.toString(), "Look up dictionary.");
                    break;

                case R.id.readFromHere:
                    Log.v(this.toString(), "Start reading from here:" + ed.getSelectionStart());
                }
                return false;
            }
        };
    }
}

我的问题:
1.如何覆盖TextView的默认行为?
2.如何通过上下文操作菜单选择文本?

1 个答案:

答案 0 :(得分:1)

如果你想在文本选择上获得自定义上下文动作模式,那么你可以像这样做

    ed = (TextView) findViewById(R.id.txtview);
    ed.setText("Hello World! Let's select some text!!");
    initActionModeCallbacks();
    ed.setTextIsSelectable(true);
    ed.setCustomSelectionActionModeCallback(mActionModeCallback);

    ed.setOnLongClickListener(new View.OnLongClickListener() {

        @Override
        public boolean onLongClick(View v) {
            Log.v(this.toString(), "Long click.");
            ed.setCursorVisible(true);
            v.setSelected(true);

            return false;
        }
    });

并在onCreateActionMode(ActionMode模式,菜单菜单)中,如果要删除标准选择项,可以调用

menu.clear();

另请注意,菜单中的项目需要有SHOW_AS_ACTION_ALWAYS标志,因为溢出按钮不起作用导致焦点更改https://stackoverflow.com/a/9883763/2751697