Webview扩展之改变字体大小

改变WebView字体大小效果：

  

直接上代码：

package com.example.zhihuibj;

import java.lang.annotation.Annotation;

import com.lidroid.xutils.view.annotation.event.OnChildClick;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.DialogInterface;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.text.AlteredCharSequence;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebSettings.TextSize;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ImageButton;
import android.widget.ProgressBar;

public class WebViewActivity extends Activity implements OnClickListener{

	private ProgressBar mProgressBar;
	private WebView mWebView;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);	
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.webview_newsdatail);
		
		 mWebView = (WebView) findViewById(R.id.wb_webview_newsdatail_webviewcontent);
		
		ImageButton mImageButton_Back = (ImageButton) findViewById(R.id.ib_webview_newsdatail_back);
		ImageButton mImageButton_textsize= (ImageButton) findViewById(R.id.ib_webview_newsdatail_textsize);
		ImageButton mImageButton_share =(ImageButton) findViewById(R.id.ib_webview_newsdatail_share);
		mProgressBar = (ProgressBar) findViewById(R.id.pb_webview_newsdatail_progressbar);
		
		  
		  mImageButton_Back.setOnClickListener(this); 
		  mImageButton_textsize.setOnClickListener(this);
		  mImageButton_share.setOnClickListener(this);
		  
		  
		  
		//根据键值获得url
		String webview_url=getIntent().getStringExtra("webview_url");//得到URL
		
		
		WebSettings webview_settings = mWebView.getSettings();
		//使能JavaScript
		webview_settings.setJavaScriptEnabled(true); 
		//显示放大缩小按钮
		webview_settings.setDisplayZoomControls(true);
		//双击放大或缩放
		webview_settings.setUseWideViewPort(true);
		
		
		
		/*
		 * 当前作用：用于获得页面加载的状态：开始加载，加载结束，在本应用中加载
		 */
		mWebView.setWebViewClient(new WebViewClient(){

			/*
			 * 所有跳转的链接都会在此回调中进行调用
			 *  */
			@Override
			public boolean shouldOverrideUrlLoading(WebView view, String url) {
				System.out.println("跳转URL ..."+url);
				view.loadUrl(url);//防止调用系统自带的浏览器打开网页
				return true;
			}

			/*
			 * 开始加载网页
			 * @see android.webkit.WebViewClient#onPageStarted(android.webkit.WebView, java.lang.String, android.graphics.Bitmap)
			 */
			@Override
			public void onPageStarted(WebView view, String url, Bitmap favicon) {
				// TODO Auto-generated method stub
				super.onPageStarted(view, url, favicon);
				System.out.println("onPageStarted.... ");
				mProgressBar.setVisibility(View.VISIBLE);
			}

			/*
			 * 加载网页结束
			 * @see android.webkit.WebViewClient#onPageFinished(android.webkit.WebView, java.lang.String)
			 */
			@Override
			public void onPageFinished(WebView view, String url) {
				// TODO Auto-generated method stub
				super.onPageFinished(view, url);
				System.out.println("onPageFinished.... ");
				mProgressBar.setVisibility(View.INVISIBLE);
			}
			
		});
		
		/*
		 * 当前作用：获得网页信息：得到网页标题，网页图标，网页加载进度
		 */
		mWebView.setWebChromeClient(new WebChromeClient(){
			/*
			 * 获得webView的标题
			 * @see android.webkit.WebChromeClient#onReceivedTitle(android.webkit.WebView, java.lang.String)
			 */
			@Override
			public void onReceivedTitle(WebView view, String title) {
				// TODO Auto-generated method stub
				super.onReceivedTitle(view, title);
				System.out.println("title : "+title);
			}
			/*
			 * 获得标题图标
			 * @see android.webkit.WebChromeClient#onReceivedIcon(android.webkit.WebView, android.graphics.Bitmap)
			 */
			@Override
			public void onReceivedIcon(WebView view, Bitmap icon) {
				// TODO Auto-generated method stub
				super.onReceivedIcon(view, icon);
			}
			/*
			 * 加载进度
			 * @see android.webkit.WebChromeClient#onProgressChanged(android.webkit.WebView, int)
			 */
			@Override
			public void onProgressChanged(WebView view, int newProgress) {
				// TODO Auto-generated method stub
				super.onProgressChanged(view, newProgress);
				System.out.println("newProgress :"+newProgress);
			}
		});		
		
		mWebView.loadUrl(webview_url);
		
	}

	@Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.ib_webview_newsdatail_back:
			finish();
			break;
		case R.id.ib_webview_newsdatail_share:
			
			break;
		case R.id.ib_webview_newsdatail_textsize:
			ChangeWebViewTextSize();
			break;
		default:
			break;
		}
		
	}

	/************************* 改变网页字体功能 开始************************************/
	private  int mCurrentDialog=0;
	private void ChangeWebViewTextSize() {

		
		AlertDialog.Builder builder = new AlertDialog.Builder(this);
		String[] items = new String[]{"超大号字体","大号字体","普通字体","小号字体","超小号字体"};
		
		builder.setTitle("设置字体");
		
		builder.setSingleChoiceItems(items,2, new DialogInterface.OnClickListener() {
			@Override
			public void onClick(DialogInterface dialog, int which) {
				mCurrentDialog=which;
				
			}
		});
		builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
			
			@Override
			public void onClick(DialogInterface dialog, int which) {
				WebSettings webview_Dialog_settings = mWebView.getSettings();
				
				switch (mCurrentDialog) {
				case 0:
					webview_Dialog_settings.setTextSize(TextSize.LARGEST);
					break;
				case 1:
					webview_Dialog_settings.setTextSize(TextSize.LARGER);
					break;
				case 2:
					webview_Dialog_settings.setTextSize(TextSize.NORMAL);
					break;
				case 3:
					webview_Dialog_settings.setTextSize(TextSize.SMALLER);
					break;
				case 4:
					webview_Dialog_settings.setTextSize(TextSize.SMALLEST);
					break;

				default:
					break;
				}
			
			}
		});
		builder.setNegativeButton("取消", new DialogInterface.OnClickListener() {
			
			@Override
			public void onClick(DialogInterface dialog, int which) {
				dialog.dismiss();
			}
		});
		builder.show();		
	}
	/************************* 改变网页字体功能 结束************************************/
}