java - 共享按钮显示为灰色并禁用

Question

我有以下代码来打开共享意图，但它被禁用并且无法单击。

@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.share, menu);

        return true;
    }
@Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home: 
                onBackPressed();
                break;
            case R.id.action_share:
                Intent share = new Intent(Intent.ACTION_SEND);
                share.setType("image/png");
                File folder = new File(Environment.getExternalStorageDirectory() + "/TESTFOLDER");
                if (!folder.exists()) {
                    folder.mkdir();
                }
                try {
                    if (file.exists()) {
                        share.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(file));
                        startActivityForResult(Intent.createChooser(share, "Share Chart"), 1);
                    }
                    else {
                        //displayToast("Please save your image before sharing.");
                    }
                }
                catch (Exception e) {
                    e.printStackTrace();
                }
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
        return true;
    }

分享xml：

<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:id="@+id/action_share"
        android:showAsAction="always"
        android:title="Share"
        android:actionProviderClass="android.widget.ShareActionProvider" />
</menu>

共享图标在我的操作栏中被禁用：

Answer 1

这不是您使用ShareActionProvider.

一旦你有数据要分享，你就会打电话setShareIntent()。ShareActionProvider这个方法接受一个Intent代表共享操作的对象——基本上就是你所拥有的share局部变量。此时，操作栏中的提供程序将是可单击的，假设您的设备上有能够根据您选择的应用程序共享的应用程序Intent。

此外，您不需要（或不想拥有）中的R.id.action_share案例onOptionsItemSelected()，因为ShareActionProvider不需要它，它可能会干扰正常操作。

例如，这里有一个活动，它实现了一个ShareActionProvider共享输入到EditText构成内容视图的文本的活动：

/***
  Copyright (c) 2013 CommonsWare, LLC
  Licensed under the Apache License, Version 2.0 (the "License"); you may not
  use this file except in compliance with the License. You may obtain   a copy
  of the License at http://www.apache.org/licenses/LICENSE-2.0. Unless required
  by applicable law or agreed to in writing, software distributed under the
  License is distributed on an "AS IS" BASIS,   WITHOUT WARRANTIES OR CONDITIONS
  OF ANY KIND, either express or implied. See the License for the specific
  language governing permissions and limitations under the License.

  From _The Busy Coder's Guide to Android Development_
    http://commonsware.com/Android
 */

package com.commonsware.android.sap;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.Menu;
import android.widget.EditText;
import android.widget.ShareActionProvider;
import android.widget.Toast;

public class MainActivity extends Activity implements
    ShareActionProvider.OnShareTargetSelectedListener, TextWatcher {
  private ShareActionProvider share=null;
  private Intent shareIntent=new Intent(Intent.ACTION_SEND);
  private EditText editor=null;

  @Override
  public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    setContentView(R.layout.activity_main);

    shareIntent.setType("text/plain");
    editor=(EditText)findViewById(R.id.editor);
    editor.addTextChangedListener(this);
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.actions, menu);

    share=
        (ShareActionProvider)menu.findItem(R.id.share)
                                 .getActionProvider();
    share.setOnShareTargetSelectedListener(this);

    return(super.onCreateOptionsMenu(menu));
  }

  @Override
  public boolean onShareTargetSelected(ShareActionProvider source,
                                       Intent intent) {
    Toast.makeText(this, intent.getComponent().toString(),
                   Toast.LENGTH_LONG).show();

    return(false);
  }

  @Override
  public void afterTextChanged(Editable s) {
    shareIntent.putExtra(Intent.EXTRA_TEXT, editor.getText());
    share.setShareIntent(shareIntent);
  }

  @Override
  public void beforeTextChanged(CharSequence s, int start, int count,
                                int after) {
    // ignored
  }

  @Override
  public void onTextChanged(CharSequence s, int start, int before,
                            int count) {
    // ignored
  }
}