APP端开发步骤

PayReq *request = [[[PayReq alloc] init] autorelease];
request.partnerId = @"10000100";
request.prepayId= @"1101000000140415649af9fc314aa427";
request.package = @"Sign=WXPay";
request.nonceStr= @"a462b76e7436e98e0ed6e13c64b4fd1c";
request.timeStamp= @"1397527777";
request.sign= @"582282D72DD2B03AD892830965F428CB16E7A256";
[WXApi sendReq：request];

-(void)onResp：(BaseResp*)resp{
  if ([respisKindOfClass：[PayRespclass]]){
      PayResp*response=(PayResp*)resp;
      switch(response.errCode){
          caseWXSuccess：
          	//服务器端查询支付通知或查询API返回的结果再提示成功
          	NSlog(@"支付成功");
          	break;
          default：
          	NSlog(@"支付失败，retcode=%d",resp.errCode);
          	break;
      }
  }
} 

IWXAPI api;
PayReq request = new PayReq();
request.appId = "wxd930ea5d5a258f4f";
request.partnerId = "1900000109";
request.prepayId= "1101000000140415649af9fc314aa427";
request.packageValue = "Sign=WXPay";
request.nonceStr= "1101000000140429eb40476f8896f4c9";
request.timeStamp= "1398746574";
request.sign= "7FFECB600D7157C5AA49810D2D8F28BC2811827B";
api.sendReq(request);

<activity
    android:name=".wxapi.WXPayEntryActivity"
    android:label="@string/app_name"
    android:theme="@android:style/Theme.Translucent.NoTitleBar"
    android:exported="true"
    android:taskAffinity="填写你的包名"
    android:launchMode="singleTask">
</activity>

public void onResp(BaseRespresp){
  	if(resp.getType()==ConstantsAPI.COMMAND_PAY_BY_WX){
  		Log.d(TAG,"onPayFinish,errCode="+resp.errCode);
  		AlertDialog.Builderbuilder=newAlertDialog.Builder(this);
  		builder.setTitle(R.string.app_tip);
  	}
}

{
  "name": "demo",
  "version": "1.0.0",
  "description": "Please describe the basic information.",
  "main": "",
  "author": "",
  "license": "",
   "dependencies": {
    "@tencent/wechat_open_sdk": "1.0.0"
  }
}

import * as wxopensdk from '@wechat/open_sdk';

// WXApi 是第三方app和微信通信的openApi接口，其实例通过WXAPIFactory获取，需要传入应用申请到的AppID
export const WXApi = wxopensdk.WXAPIFactory.createWXAPI(APP_ID)

// WXApiEventHandler为微信数据的回调
class WXApiEventHandlerImpl implements wxopensdk.WXApiEventHandler {
  private onReqCallbacks: Map<OnWXReq, OnWXReq> = new Map
  private onRespCallbacks: Map<OnWXResp, OnWXResp> = new Map

  registerOnWXReqCallback(on: OnWXReq) {
    this.onReqCallbacks.set(on, on)
  }
  unregisterOnWXReqCallback(on: OnWXReq) {
    this.onReqCallbacks.delete(on)
  }

  registerOnWXRespCallback(on: OnWXResp) {
    this.onRespCallbacks.set(on, on)
  }
  unregisterOnWXRespCallback(on: OnWXResp) {
    this.onRespCallbacks.delete(on)
  }

  onReq(req: wxopensdk.BaseReq): void {
    Log.i(kTag, "onReq:%s", JSON.stringify(req))
    this.onReqCallbacks.forEach((on) => {
      on(req)
    })
  }

  onResp(resp: wxopensdk.BaseResp): void {
    Log.i(kTag, "onResp:%s", JSON.stringify(resp))
    this.onRespCallbacks.forEach((on) => {
      on(resp)
    })
  }
}
export const WXEventHandler = new WXApiEventHandlerImpl

//调用支付
let req = new wxopensdk.PayReq
req.appId = 'wxd930ea5d5a258f4f'//微信开放平台审核通过的移动应用AppID
req.partnerId = '1900000109'//微信支付商户号
req.prepayId = '1101000000140415649af9fc314aa427'//调用微信支付下单接口返回的支付交易会话ID
req.packageValue = 'Sign=WXPay'//填写固定值Sign=WXPay
req.nonceStr = '1101000000140429eb40476f8896f4c9'//随机字符串，不长于32位
req.timeStamp = '1398746574'//时间戳
req.sign = '7FFECB600D7157C5AA49810D2D8F28BC2811827B'//签名值
// 向微信发送登录请求:
//   context为ohos内置类，app间跳转需依赖该类，开发者可在Component中获取
//   finished为跳转微信的结果：true表示跳转成功；false表示跳转失败，可能是因为微信未安装
let finished = await this.wxApi.sendReq(context: common.UIAbilityContext, req)


// 在EntryAbility中响应来自微信的回调
export default class EntryAbility extends UIAbility {
  onCreate(want: Want, _launchParam: AbilityConstant.LaunchParam): void {
    this.handleWeChatCallIfNeed(want)
  }
  
  onNewWant(want: Want, _launchParam: AbilityConstant.LaunchParam): void {
    this.handleWeChatCallIfNeed(want)
  }

  private handleWeChatCallIfNeed(want: Want) {
    WXApi.handleWant(want, WXEventHandler)
  }
}

onResp(resp: wxopensdk.BaseResp): void {
Log.i(kTag, "onResp:%s", JSON.stringify(resp))
 this.onRespCallbacks.forEach((on) => {
 on(resp)
 })
 }