使用以下代码示例来设置Webview的高度和宽度：

WebView myWebView = findViewById(R.id.webview);//请根据您的Webview的id进行更改
DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
int width = displayMetrics.widthPixels;
int height = displayMetrics.heightPixels;
myWebView.setInitialScale(1);
myWebView.getSettings().setLoadWithOverviewMode(true);
myWebView.getSettings().setUseWideViewPort(true);
myWebView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);
myWebView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
myWebView.measure(width, height);
myWebView.layout(0, 0, width, height);