狂刷Android范例之二：剪贴板范例ClipboardSample

说明

狂刷Android范例系列文章开张了。每篇学习一个Android范例，将一个范例单独生成一个可运行的app，并对重点源代码进行简要分析。然后提供打包好的源代码下载。

功能

功能很简单，使用Android提供的剪贴板，复制不同类型的数据到剪贴板。
代码包在此，无需下载分：
http://download.csdn.net/detail/logicteamleader/8786187

来源

ClipboardSample例子来自于Android-20的com.example.android.apis.content.ClipboardSample。

环境

代码运行环境：
1.ADT2014版本；
2.android:minSdkVersion=”16”；android:targetSdkVersion=”20”
3.workspace中已经生成了appcompatv7，它的版本是android-22；

代码

注意几个重点的类和方法：剪贴板管理器ClipboardManager，切片数据类ClipData，数组适配器类ArrayAdapter，getSystemService(CLIPBOARD_SERVICE)方法。
其他内容研究代码即可。

/**
 * Copyright (c) 2010, The Android Open Source Project
 *
 * 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.
 */

package com.example.clipboardsample;

import android.app.Activity;
import android.content.ClipData;
import android.content.ClipboardManager;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.text.method.LinkMovementMethod;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.TextView;

public class ClipboardSample extends Activity {
    ClipboardManager mClipboard;

    Spinner mSpinner;
    TextView mMimeTypes;
    TextView mDataText;

    CharSequence mStyledText;
    String mPlainText;
    String mHtmlText;
    String mHtmlPlainText;

    ClipboardManager.OnPrimaryClipChangedListener mPrimaryChangeListener
            = new ClipboardManager.OnPrimaryClipChangedListener() {
        public void onPrimaryClipChanged() {
            updateClipData(true);
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

//        通过getSystemService(CLIPBOARD_SERVICE)得到剪切板管理器
        mClipboard = (ClipboardManager)getSystemService(CLIPBOARD_SERVICE);

        // See res/any/layout/resources.xml for this view layout definition.
        setContentView(R.layout.clipboard);

        TextView tv;

        mStyledText = getText(R.string.styled_text);
        tv = (TextView)findViewById(R.id.styled_text);
        tv.setText(mStyledText);

        mPlainText = mStyledText.toString();
        tv = (TextView)findViewById(R.id.plain_text);
        tv.setText(mPlainText);

        mHtmlText = "<b>Link:</b> <a href=\"http://www.android.com\">Android</a>";
        mHtmlPlainText = "Link: http://www.android.com";
        tv = (TextView)findViewById(R.id.html_text);
        tv.setText(mHtmlText);

        mSpinner = (Spinner) findViewById(R.id.clip_type);

        //这三行代码创建了一个Spinner使用的经典ArrayAdapter，其中用到了资源文件R.array.clip_data_types
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(
                this, R.array.clip_data_types, android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        mSpinner.setAdapter(adapter);

        mSpinner.setOnItemSelectedListener(
                new OnItemSelectedListener() {
                    public void onItemSelected(
                            AdapterView<?> parent, View view, int position, long id) {
                        updateClipData(false);
                    }
                    public void onNothingSelected(AdapterView<?> parent) {
                    }
                });

        mMimeTypes = (TextView)findViewById(R.id.clip_mime_types);
        mDataText = (TextView)findViewById(R.id.clip_text);

        mClipboard.addPrimaryClipChangedListener(mPrimaryChangeListener);
        updateClipData(true);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mClipboard.removePrimaryClipChangedListener(mPrimaryChangeListener);
    }

    public void pasteStyledText(View button) {
        mClipboard.setPrimaryClip(ClipData.newPlainText("Styled Text", mStyledText));
    }

    public void pastePlainText(View button) {
        mClipboard.setPrimaryClip(ClipData.newPlainText("Styled Text", mPlainText));
    }

    public void pasteHtmlText(View button) {
        mClipboard.setPrimaryClip(ClipData.newHtmlText("HTML Text", mHtmlPlainText, mHtmlText));
    }

    public void pasteIntent(View button) {
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.android.com/"));
        mClipboard.setPrimaryClip(ClipData.newIntent("VIEW intent", intent));
    }

    public void pasteUri(View button) {
        mClipboard.setPrimaryClip(ClipData.newRawUri("URI", Uri.parse("http://www.android.com/")));
    }

//    更新剪切板内容的函数
    void updateClipData(boolean updateType) {
        ClipData clip = mClipboard.getPrimaryClip();
        String[] mimeTypes = clip != null ? clip.getDescription().filterMimeTypes("*/*") : null;
        if (mimeTypes != null) {
            mMimeTypes.setText("");
            for (int i=0; i<mimeTypes.length; i++) {
                if (i > 0) {
                    mMimeTypes.append("\n");
                }
                mMimeTypes.append(mimeTypes[i]);
            }
        } else {
            mMimeTypes.setText("NULL");
        }

        if (updateType) {
            if (clip != null) {
                ClipData.Item item = clip.getItemAt(0);
                if (item.getHtmlText() != null) {
                    mSpinner.setSelection(2);
                } else if (item.getText() != null) {
                    mSpinner.setSelection(1);
                } else if (item.getIntent() != null) {
                    mSpinner.setSelection(3);
                } else if (item.getUri() != null) {
                    mSpinner.setSelection(4);
                } else {
                    mSpinner.setSelection(0);
                }
            } else {
                mSpinner.setSelection(0);
            }
        }

        if (clip != null) {
            ClipData.Item item = clip.getItemAt(0);
            switch (mSpinner.getSelectedItemPosition()) {
                case 0:
                    mDataText.setText("(No data)");
                    break;
                case 1:
                    mDataText.setText(item.getText());
                    break;
                case 2:
                    mDataText.setText(item.getHtmlText());
                    break;
                case 3:
                    mDataText.setText(item.getIntent().toUri(0));
                    break;
                case 4:
                    mDataText.setText(item.getUri().toString());
                    break;
                case 5:
                    mDataText.setText(item.coerceToText(this));
                    break;
                case 6:
                    mDataText.setText(item.coerceToStyledText(this));
                    break;
                case 7:
                    mDataText.setText(item.coerceToHtmlText(this));
                    break;
                default:
                    mDataText.setText("Unknown option: " + mSpinner.getSelectedItemPosition());
                    break;
            }
        } else {
            mDataText.setText("(NULL clip)");
        }
        mDataText.setMovementMethod(LinkMovementMethod.getInstance());
    }
}