WebView 加载判断 和 加载动画的简单实现

WebView 在加载网页时候，在网络不好的情况下，如果不做处理会出现一段时间的等待空白，用户体验差。所以有必要加上一个简单的加载进度提示。本编简单的运用了ProgressDialog 这个控件来实现。

下面是简单的代码片段

下面贴上部分代码

public class FAQActivity extends BaseActivity {

private final String TAG = FAQActivity.class.getName();

@BindView(R.id.activity_fap_back)

ImageView activityFapBack;

@BindView(R.id.activity_faq_webview)

WebView webView;

private String FAQ_BASE_URL = "";

/***

*

* @param savedInstanceState

*/

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_faq);

ButterKnife.bind(this);

init();

}

private void init() {

webView.loadUrl("你的请求地址");

WebSettings mWebSettings = webView.getSettings();

mWebSettings.setSupportZoom(true);

mWebSettings.setLoadWithOverviewMode(true);

mWebSettings.setUseWideViewPort(true);

mWebSettings.setDefaultTextEncodingName("GBK");//设置解码格式

mWebSettings.setLoadsImagesAutomatically(true);

mWebSettings.setJavaScriptEnabled(true);//支持js 特效

//覆盖WebView默认使用第三方或系统默认浏览器打开网页的行为，使网页用WebView打开

webView.setWebViewClient(new WebViewClient() {

@Override

public boolean shouldOverrideUrlLoading(WebView view, String url) {

// TODO Auto-generated method stub

//返回值是true的时候控制去WebView打开，为false调用系统浏览器或第三方浏览器

view.loadUrl(url);

return true;

}

@Override

public void onPageStarted(WebView view, String url, Bitmap favicon) {

super.onPageStarted(view, url, favicon);

showProgress("页面加载中");//开始加载动画

}

@Override

public void onPageFinished(WebView view, String url) {

super.onPageFinished(view, url);

removeProgress();//当加载结束时移除动画

}

});

}

/**

* 点击事件

*/

@OnClick(R.id.activity_fap_back)

public void onClick() {

Log.d(TAG, "onClick: ");

jumpToActivity(FAQActivity.this,MenuActivity.class);

}

/**

* 返回键的监听事件

*

* @param keyCode

* @param event

* @return

*/

public boolean onKeyDown(int keyCode, KeyEvent event) {

if (keyCode == KeyEvent.KEYCODE_BACK) {

jumpToActivity(FAQActivity.this,MenuActivity.class);

}

return false;

}

}

需要注意的地方:

ProgressDIalog 控件为了不写重复代码，我进行了简单的封装。下面是我简单封装的BaseActivity代码

public class BaseActivity extends AppCompatActivity {

private final String TAG = BaseActivity.class.getName();

private Toast toast = null;

private ProgressDialog progressDialog;

@Override

protected void onCreate(@Nullable Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

}

/**

* @param context 上下文对象

* @param start 其实activity

* @param target 目标activity

*/

public void jumpToActivity(Context context, Class start, Class target) {

Intent intent = new Intent(context, target);

//------用户返回上一级activity

if (target == CarFindingActivity.class) {

intent.putExtra("activity", start);

}

context.startActivity(intent);

finish();

}

public void jumpToActivity(Context context, Class target) {

Intent intent = new Intent(context, target);

//------用户返回上一级activity

context.startActivity(intent);

finish();

}

/**

* @param context

* @param text

*/

public void showToastLong(Context context, String text) {

if (toast == null) {

toast = Toast.makeText(context, text, Toast.LENGTH_LONG);

} else {

toast.setText(text);

}

toast.show();

}

public void showToastLong(String text) {

if (toast == null) {

toast = Toast.makeText(BaseActivity.this, text, Toast.LENGTH_LONG);

} else {

toast.setText(text);

}

toast.show();

}

/**

* @param context

* @param text

*/

public void showToastShort(Context context, String text) {

if (toast == null) {

toast = Toast.makeText(context, text, Toast.LENGTH_SHORT);

} else {

toast.setText(text);

}

toast.show();

}

public void showToastShort(String text) {

if (toast == null) {

toast = Toast.makeText(BaseActivity.this, text, Toast.LENGTH_SHORT);

} else {

toast.setText(text);

}

toast.show();

}

//-----显示ProgressDialog

public void showProgress(String message) {

if (progressDialog == null) {

progressDialog = new ProgressDialog(BaseActivity.this, ProgressDialog.STYLE_SPINNER);

progressDialog.setCancelable(false);//设置点击不消失

}

if (progressDialog.isShowing()) {

progressDialog.setMessage(message);

} else {

progressDialog.setMessage(message);

progressDialog.show();

}

}

//------取消ProgressDialog

public void removeProgress(){

if (progressDialog==null){

return;

}

if (progressDialog.isShowing()){

progressDialog.dismiss();

}

}

/**

*

*/

@Override

protected void onStart() {

super.onStart();

Log.d(TAG, "onStart: ");

}

@Override

protected void onResume() {

super.onResume();

Log.d(TAG, "onResume: ");

}

@Override

protected void onPause() {

super.onPause();

Log.d(TAG, "onPause: ");

}

@Override

protected void onStop() {

removeProgress();//让progressdialog 消失

super.onStop();

Log.d(TAG, "onStop: ");

}

@Override

protected void onRestart() {

super.onRestart();

Log.d(TAG, "onRestart: ");

}

@Override

protected void onDestroy() {

super.onDestroy();

Log.d(TAG, "onDestroy: ");

}

}

然后继承BaseActivtiy 直接调用里面

showProgress(String message)

显示ProgressDialog

removeProgress()

移除ProgressDialog

以上就这么多，如有错误或者不严谨的地方恳请指正,谢谢