RichTextEditor
iOS 13 之后不再支持 UIWebView,所以将之前一篇文章iOS 富文本编辑器-UIWebView中 UIWebView 替换为 WKWebView。以下为更换到 WKWebView 的一些知识点。
富文本编辑器设计的知识点
Objective-C 语言调用 JavaScript 语言
通过WKWebView的
- (void)evaluateJavaScript:(NSString *)javaScriptString completionHandler:(void (^ _Nullable)(_Nullable id, NSError * _Nullable error))completionHandler;
方法来实现的。这样我们就可以实现文字的加粗、下划线、斜体等等一切我们想要的样式。
详见项目中 WKWebView+VJJSTool 文件。
JavaScript 语言调用 Objective-C 语言
第一步：我们需要在WKWebView创建的过程中初始化添加ScriptMessageHandler
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
WKUserContentController *userController = [[WKUserContentController alloc] init];
configuration.userContentController = userController;
_mainWebView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, KMainWidth, KMainHeight) configuration:configuration];
[userController addScriptMessageHandler:self name:@"currentCookies"];
然后实现代理方法.监听JS的回调.
//JS调用的OC回调方法
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message{
if ([message.name isEqualToString:@"jsMethod"]) {
//
}
}
然后在Html文件中添加点击方法.
<div id="button_div" onclick="buttonDivAction()">
点击调用OC方法
</div>
紧接着.在js文件中实现点击事件.这时候要注意的是ScriptMessageHandler的名称要与上面定义的一致.
function buttonDivAction() {
window.webkit.messageHandlers. jsMethod.postMessage({
"body": "buttonActionMessage"
});
}
输入文字时，插入符号位置计算
ZSSRichTextEditor.js
zss_editor.calculateEditorHeightWithCaretPosition = function() {}
新增标题与副标题
editor.html
<div id="vj_title">
<input id="vj_article_title" maxlength="70" type="text" placeholder="请输入标题">
</div>
<div id="vj_abstract-title">
<input id="vj_article_abstract" maxlength="35" type="text" placeholder="请输入文章摘要">
</div>
去掉键盘自带的工具条
WKWebView+HackishAccessoryHiding.h
@property (nonatomic, assign) BOOL hidesInputAccessoryView;
自动弹出键盘
实现和 UIWebView 中 keyboardDisplayRequiresUserAction 相同功能。即在 web 页面 focus 获得焦点状态下弹出键盘，UIWebView 中 keyboardDisplayRequiresUserAction 设置为 NO 就可以实现，但是WKWebView 中没有此属性，可以通过以下方式实现：
WKWebView+HackishAccessoryHiding.m
-(void)allowDisplayingKeyboardWithoutUserAction {
Class class = NSClassFromString(@"WKContentView");
NSOperatingSystemVersion iOS_11_3_0 = (NSOperatingSystemVersion){11, 3, 0};
NSOperatingSystemVersion iOS_12_2_0 = (NSOperatingSystemVersion){12, 2, 0};
NSOperatingSystemVersion iOS_13_0_0 = (NSOperatingSystemVersion){13, 0, 0};
char * methodSignature = "_startAssistingNode:userIsInteracting:blurPreviousNode:changingActivityState:userObject:";
if ([[NSProcessInfo processInfo] isOperatingSystemAtLeastVersion: iOS_13_0_0]) {
methodSignature = "_elementDidFocus:userIsInteracting:blurPreviousNode:activityStateChanges:userObject:";
} else if ([[NSProcessInfo processInfo] isOperatingSystemAtLeastVersion: iOS_12_2_0]) {
methodSignature = "_elementDidFocus:userIsInteracting:blurPreviousNode:changingActivityState:userObject:";
}
if ([[NSProcessInfo processInfo] isOperatingSystemAtLeastVersion: iOS_11_3_0]) {
SEL selector = sel_getUid(methodSignature);
Method method = class_getInstanceMethod(class, selector);
IMP original = method_getImplementation(method);
IMP override = imp_implementationWithBlock(^void(id me, void* arg0, BOOL arg1, BOOL arg2, BOOL arg3, id arg4) {
((void (*)(id, SEL, void*, BOOL, BOOL, BOOL, id))original)(me, selector, arg0, TRUE, arg2, arg3, arg4);
});
method_setImplementation(method, override);
} else {
SEL selector = sel_getUid("_startAssistingNode:userIsInteracting:blurPreviousNode:userObject:");
Method method = class_getInstanceMethod(class, selector);
IMP original = method_getImplementation(method);
IMP override = imp_implementationWithBlock(^void(id me, void* arg0, BOOL arg1, BOOL arg2, id arg3) {
((void (*)(id, SEL, void*, BOOL, BOOL, id))original)(me, selector, arg0, TRUE, arg2, arg3);
});
method_setImplementation(method, override);
}
}
详细代码请看项目 https://github.com/Vergil-wj/RichTextEditor
参考资料：
