Android WebView 设置加载动画

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

<span style="color:#ff6666;"><</span>?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <android.support.v7.widget.Toolbar        android:background="@color/colorPrimaryDark"        android:popupTheme="@style/AppTheme.PopupOverlay"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:minHeight="?attr/actionBarSize"      >        <ImageView            android:id="@+id/faq_activity_back"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:src="@mipmap/back"/>        <TextView            android:id="@+id/faq_activity_title"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:layout_gravity="center_horizontal"            android:textColor="@color/white"            android:textSize="22sp"            android:text="常见问题"            />    </android.support.v7.widget.Toolbar>    <WebView        android:id="@+id/faq_webview"        android:layout_width="match_parent"        android:layout_height="match_parent" /></LinearLayout>

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